Pain

type of unpleasant feeling
(Redirected from Agonising)

Pain is an unpleasant sensation which may be associated with actual or potential tissue damage and which may have physical and emotional components.

The sword of time will pierce our skin
It doesn't hurt when it begins
But as it works its way on in
The pain grows stronger watch I bring
That suicide is painless
It brings so many changes
And I can take or leave them if I please. ~ Mike Altman
[F]alling from the stars: Drenched in my pain again; becoming who we are. ~ Billie Joe Armstrong

Quotes

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Sunny days wouldn't be special if it wasn't for rain; joy wouldn't feel so good if it wasn't for pain. ~ 50 Cent
 
Maybe take a breath; maybe do it twice. I know you're in pain, but that's a part of life. ~ Em Beihold
  • Sunny days wouldn't be special if it wasn't for rain; joy wouldn't feel so good if it wasn't for pain.
  • The pain was what it was. Beyond that there is nothing to say. Qualities of feeling are as incomparable as they are indescribable. They mark the limit of the capacity of language to communicate. If someone wanted to impart his physical pain, he would be forced to inflict it and thereby become a torturer himself.
    • Jean Améry, At the Mind’s Limits: Contemplations by a Survivor on Auschwitz and Its Realities (1966)
  • Pain is temporary, glory is forever.
    • Anonymous, quoted as an anonymous proverb in Preaching Proverbs : Wisdom for the Pulpit‎ (1996) by Alyce M. McKenzie, p. 84.
  • Pain is weakness leaving the body.
  • You think your pain and your heartbreak are unprecedented in the history of the world, but then you read. It was Dostoevsky and Dickens who taught me that the things that tormented me most were the very things that connected me with all the people who were alive, or who ever had been alive. Only if we face these open wounds in ourselves can we understand them in other people.
    • James Baldwin as quoted in "Doom and glory of knowing who you are" by Jane Howard, in LIFE magazine, Vol. 54, No. 21 (24 May 1963), p. 89
  • Maybe life is good and everything is fine. Maybe take a breath; maybe do it twice. I know you're in pain, but that's a part of life.
  • PAIN, n. An uncomfortable frame of mind that may have a physical basis in something that is being done to the body, or may be purely mental, caused by the good fortune of another.
  • In this last context, food refusal, weight loss, commitment to exercise, and ability to tolerate bodily pain and exhaustion have become cultural metaphors for self-determination, will, and moral fortitude.
  • According to the doctrine of informed consent, even when it is “for the good” of the patient no one else-neither relative nor expert-may determine for the embodied subject that medical risks are worth taking, what procedures are minimally or excessively invasive, what pain is minor.
  • Whether, and at what stage a fetus feels pain has been a matter of much debate. The RCOG 2022 report Fetal Awareness Evidence Review concluded that the “evidence indicates that the possibility of pain perception before 28 weeks of gestation is unlikely”.
    The BMA recommends that doctors should give due consideration to the appropriate measures for minimising the risk of pain, including assessment of the most recent evidence. The BMA suggests that even if there is no incontrovertible evidence that the fetus feels pain, the use of fetal analgesia when carrying out any procedure (whether an abortion or a therapeutic intervention) on the fetus in utero may go some way in relieving the anxiety of the woman and health professionals.
  • But pain... seems to me an insufficient reason not to embrace life. Being dead is quite painless. Pain, like time, is going to come on regardless. Question is, what glorious moments can you win from life in addition to the pain?
  • If everyone could feel everyone else’s pain, who would torture?
  • Beauty is pain and there's beauty in everything, what's a little bit of hunger? I can go a little while longer.
  • Douleur toujours nouvelle pour celui qui souffre et qui se banalise pour l'entourage.
    • Pain is always new to the sufferer, but loses its originality for those around him.
    • Alphonse Daudet, La doulou: (la douleur), 1887-1895 (Paris: Librairie de France, 1930) p. 16; Julian Barnes (ed. and trans.) In the Land of Pain (New York: Alfred A. Knopf, 2002) p. 19.
  • In a universe of blind physical forces and genetic replication, some people are going to get hurt, other people are going to get lucky, and you won’t find any rhyme or reason in it, nor any justice.
  • It never occurred to me to call 911 or my physician. […] As foolish as it may appear, you are, in a sense, a prisoner of the pain, which was intolerable. You're thinking, what could I do to relieve myself of it. If it becomes intense enough, you're perfectly willing to accept cardiac arrest as a possible way of getting rid of the pain.
  • Wait another minute, can't you see what this pain has fucking done to me? I'm alive and still kicking.
  • So great was the extremity of his pain and anguish, that he did not only sigh but roar.
  • Pain is just Mother Nature’s little way of telling you not to do something again in a way you’ll remember.
    • Tim Huntley, One on Me (1980), Chapter 11
  • The multidimensionality of pain perception, involving sensory, emotional, and cognitive factors may in itself be the basis of conscious, painful experience, but it will remain difficult to attribute this to a fetus at any particular developmental age.
    • Johnson, Martin; Everitt, Barry (2000). Essential reproduction. Blackwell. p. 216. ISBN 9780632042876. Retrieved 21 February 2007.
  • Tell me your relation to pain, and I will tell you who you are!
  • One focus for the discussion of the 'problem' of late abortion has been based on the claim that a fetus feels pain. The debate about fetal pain originated with discussion which began in the late 1980s, as a consequence of research which indicated that a fetus is capable of a behavioral response to sensory stimulation.
    Advances in fetal surgery, which include placing valves into the heart and injecting red blood cells into the liver to prevent anaemia, meant that neonatal surgeons and experts in embryology were becoming more and more concerned about the potential consequences of invasive fetal surgery. This concern was given a major boost when Dr Anand, then of the John Radcliffe Hospital, Oxford, demonstrated that new-born babies (neonates) undergoing surgery did better if they were given anaesthetics of a kind usually used only in adult surgery (until very recently, neonates were not given anaesthetic before surgery). In 1992, the New England Journal ran an editorial calling on clinicians to 'Do the Right Thing' concluding that 'it is our responsibility to treat pain in neonates and infants as effectively as we do in other patients'. Since this time, and extensive discussion has taken place in the pages of medical journals, about the nature of pain, with many eminent scientists concluding that they have much more to learn about this phenomenon.
    Greater knowledge about the causes of pain can only be beneficial to society, and it is important that clinicians do 'do the right thing' where neonates and infants are concerned. It is however extremely unfortunate that a discussion about best clinical practice for new-born babies has led to a debate, based on the notion that a fetus can feel pain, about the 'problem' of late abortion.
  • Issues associated with the science of pain have been discussed extensively elsewhere. For the purposes of this briefing we will simply state our position very briefly. The ascribing of the term 'pain' to the responses of a fetus to stimuli is perhaps best understood as an emotional process on the part of those who do so, rather than an objective analysis of pain. Since a fetus moves, or screws up its face, it can appear to be 'suffering pain'. However, the fact that no-one has any memory of being born - which if a fetus can indeed feel pain would be expected to be a very painful process indeed - suggests that there is a great deal of difference between what might look like pain, and what the experience in fact constitutes. What needs to be said is that fetuses do not, an cannot, feel pain - not at 10 weeks, 26 weeks or 30 weeks - because pain-experience depends on consciousness and fetuses are not conscious.
  • pain acts like a leaven for both word and thought, quickening your sense of reality and the true logic of this world. Without pain you cannot distinguish the creative element that builds and sustains life from its opposite-the forces of death and destruction which are always for some reason very seductive, seeming at first sight to be logically plausible, and perhaps even irresistible.
    • Nadezhda Mandelstam Hope Abandoned (1974) chapter 1, Translated from the Russian by Max Hayward
  • The term 'psychogenic' assumes that medical diagnosis is so perfect that all organic causes of pain can be detected; regrettably, we are far from such infallibility... All too often, the diagnosis of neurosis as the cause of pain hides our ignorance of many aspects of pain medicine.
  • Doctors should not be required to discuss fetal pain with women seeking abortions because fetuses likely can’t feel pain until late in pregnancy, according to a review critics say hardly settles the contentious topic.
    Researchers at the University of California, San Francisco reviewed dozens of studies and medical reports and said the data indicate that fetuses likely are incapable of feeling pain until around the seventh month of pregnancy, when they are about 28 weeks old.
    Based on the evidence, discussions of fetal pain for abortions performed before the end of the second trimester should not be mandatory, according to the study appearing in Wednesday’s Journal of the American Medical Association.
    The review, researchers say, is an attempt to present a comprehensive, objective report on evidence to inform the debate over fetal pain laws aimed at making women think twice before getting abortions.
    Critics angrily disputed the findings and claimed the report is biased.
    “They have literally stuck their hands into a hornet’s nest,” said Dr. Kanwaljeet Anand, a fetal pain researcher at the University of Arkansas for Medical Sciences, who believes fetuses as young as 20 weeks old feel pain. “This is going to inflame a lot of scientists who are very, very concerned and are far more knowledgeable in this area than the authors appear to be. This is not the last word — definitely not.”
  • Proposed federal legislation would require doctors to provide fetal pain information to women seeking abortions when fetuses are at least 20 weeks old, and to offer women fetal anesthesia at that stage of the pregnancy. A handful of states have enacted similar measures.
    The review says medical evidence shows that brain structures involved in feeling pain begin forming earlier but likely do not function until around the seventh month, when fetuses are about 28 weeks old.
    Some scientists say younger fetuses show pain by moving away from a stimulus, but that likely is a reflex action and not an indication that they are actually feeling pain, said UCSF obstetric anesthesiologist Dr. Mark Rosen, the study’s senior author.
    Offering fetal pain relief in the fifth or sixth month, when brains are too immature to feel pain, is misguided and might result in unacceptable health risks to women, the authors said.
    Dr. Nancy Chescheir, chairman of obstetrics and gynecology at Vanderbilt University and a board director at the Society of Maternal-Fetal Medicine, said the report “will help to develop some consensus” on when fetuses feel pain. “To date, there hasn’t been any.”
  • For I consider that the sufferings of the present time do not amount to anything in comparison with the glory that is going to be revealed in us. For the creation is waiting with eager expectation for the revealing of the sons of God. For the creation was subjected to futility, not by its own will, but through the one who subjected it, on the basis of hope that the creation itself will also be set free from enslavement to corruption and have the glorious freedom of the children of God. For we know that all creation keeps on groaning together and being in pain together until now.
  • There is an art in taking the whiplash of suffering full in the face, an art you must learn. Let each single attack exhaust itself; pain always makes single attacks, so that its bite may be more intense, more concentrated. And you, while its fangs are implanted and injecting their venom at one spot, do not forget to offer it another place where it can bite you, and so relieve the pain of the first.
  • Now, all of this raises important questions about what one means by "evidence,"or "medical information,"because the ultra-sound image is presented as a document testifying that the fetus is "alive," is "human like you or me,"and "senses pain.""The Silent Scream has been sharply confronted on this level by panels of opposing medical experts, New York Times editorials, and a Planned Parenthood film. These show, for example,that at twelve weeks the fetus has no cerebral cortex to receive pain impulses;that no "scream"is possible without air in the lungs;that fetal movements at this stage are reflexive and without purpose;that the image of rapid frantic movement was undoubtedly caused by speeding up the film (cameratricks);that the size of the image we see on the screen, along with the model that is continually displayed in front of the screen, is nearly twice the size of a normal twelve-week fetus, and so forth.
  • A portion of life, every moment gets torn out of me hurting, and flees away.
  • My heart itself is a wound,
    no medicine can cure it.
    It deepens further if stared at,
    and hurts more if touched.
  • “A 20-week fetal pain bill is actually teaching people that it’s OK to kill children under 20 weeks,” said Ragon. “The incrementalism actually even teaches people that that’s morality. Because some people, unfortunately, derive their morality from the legislation that goes on around them. It’s supposed to be the other way around.”
  • Editor-Peter McCullagh and P J Saunders link the theoretical possibility that the fetus may feel pain (albeit much earlier than most embryologists and physiologists consider likely) with the procedure of legal abortion. Doctors for a Woman's Choice on Abortion consider this to be unhelpful to women and to the scientific debate.
    In Britain virtually all surgical terminations of pregnancy take place under general anaesthesia, which will affect the fetus. The question of whether the fetus experiences pain is not an issue as far as abortion is concerned, although those experts in fetomaternal medicine who are operating on the more mature fetus in utero need to consider whether women should have general anaesthesia for these procedures.
  • Though free to think and act, we are held together, like the stars in the firmament, with ties inseparable. These ties cannot be seen, but we can feel them. I cut myself in the finger, and it pains me: this finger is a part of me. I see a friend hurt, and it hurts me, too: my friend and I are one. And now I see stricken down an enemy, a lump of matter which, of all the lumps of matter in the universe, I care least for, and it still grieves me. Does this not prove that each of us is only part of a whole?
    For ages this idea has been proclaimed in the consummately wise teachings of religion, probably not alone as a means of insuring peace and harmony among men, but as a deeply founded truth. The Buddhist expresses it in one way, the Christian in another, but both say the same: We are all one.
  • The pain that you create now is always some form of non acceptance, some form of unconscious resistance to what is. On the level of thought, the resistance is some form of judgment. On the emotional level, it is some form of negativity. The intensity of the pain depends on the degree of resistance to the present moment, and this in turn depends on how strongly you are identified with your mind. The mind always seeks to deny the Now and to escape from it. In other words, the more you are identified with your mind, the more you suffer. Or you may put it like this: the more you are able to honor and accept the Now, the more you are free of pain, of suffering - and free of the egoic mind.
    • Eckhart Tolle in The Power of Now: A Guide to Spiritual Enlightenment (1997) p. 26
  • When you create a problem, you create pain. All it takes is a simple choice, a simple decision: no matter what happens, I will create no more pain for myself. I will create no more problems. Although it is a simple choice, it is also very radical. You won' t make that choice unless you are truly fed up with suffering, unless you have truly had enough. And you won't be able to go through with it unless you access the power of the Now. If you create no more pain for yourself, then you create no more pain for others. You also no longer contaminate the beautiful Earth, your inner space, and the collective human psyche with the negativity of problem-making.
    If you have ever been in a life-or-death emergency situation, you will know that it wasn't a problem. The mind didn't have time to fool around and make it into a problem. In a true emergency, the mind stops; you become totally present in the Now, and something infinitely more powerful takes over. This is why there are many reports of ordinary people suddenly becoming capable of incredibly courageous deeds. In any emergency, either you survive or you don't. Either way, it is not a problem.
  • Your unhappiness is polluting not only your own inner being and those around you but also the collective human psyche of which you are an inseparable part. The pollution of the planet is only an outward reflection of an inner psychic pollution: millions of unconscious individuals not taking responsibility for their inner space. Either stop doing what you are doing, speak to the person concerned and express fully what you feel, or drop the negativity that your mind has created around the situation and that serves no purpose whatsoever except to strengthen a false sense of self. Recognizing its futility is important. Negativity is never the optimum way of dealing with any situation. In fact, in most cases it keeps you stuck in it, blocking real change. Anything that is done with negative energy will become contaminated by it and in time give rise to more pain, more unhappiness. Furthermore, any negative inner state is contagious: Unhappiness spreads more easily than a physical disease. Through the law of resonance, it triggers and feeds latent negativity in others, unless they are immune - that is, highly conscious. Are you polluting the world or cleaning up the mess? You are responsible for your inner space; nobody else is...
  • Deep unconsciousness, such as the pain-body, or other deep pain, such as the loss of a loved one, usually needs to be transmuted through acceptance combined with the light of your presence - your sustained attention. Many patterns in ordinary unconsciousness, on the other hand, can simply be dropped once you know that you don't want them and don't need them anymore, once you realize that you have a choice, that you are not just a bundle of conditioned reflexes. All this implies that you are able to access the power of Now. Without it, you have no choice.
  • Apart from her personal pain-body, every woman has her share in what could be described as the collective female pain-body - unless she is fully conscious. This consists of accumulated pain suffered by women partly through male subjugation of the female, through slavery, exploitation, rape, childbirth, child loss, and so on, over thousands of years. The emotional or physical pain that for many women precedes and coincides with the menstrual flow is the pain-body in its collective aspect that awakens from its dormancy at that time, although it can be triggered at other times too. It restricts the free flow of life energy through the body, of which menstruation is a physical expression... Often a woman is "taken over" by the pain-body at that time. It has an extremely powerful energetic charge that can easily pull you into unconscious identification with it. You are then actively possessed by an energy field that occupies your inner space and pretends to be you - but, of course, is not you at all. It speaks through you, acts through you, thinks through you. It will create negative situations in your life so that it can feed on the energy. It wants more pain, in whatever form... It is pure pain, past pain - and it is not you... The number of women who are now approaching the fully conscious state already exceeds that of men and will be growing even faster in the years to come. p. 106
  • The pain that you create now is always some form of non acceptance, some form of unconscious resistance to what is. On the level of thought, the resistance is some form of judgment. On the emotional level, it is some form of negativity. The intensity of the pain depends on the degree of resistance to the present moment, and this in turn depends on how strongly you are identified with your mind. The mind always seeks to deny the Now and to escape from it. In other words, the more you are identified with your mind, the more you suffer. Or you may put it like this: the more you are able to honor and accept the Now, the more you are free of pain, of suffering - and free of the egoic mind.
    • Eckhart Tolle in The Power of Now: A Guide to Spiritual Enlightenment (1997)
  • The beginning of freedom from the painbody lies first of all in the realization that you have a painbody. Then, more important, in your ability to stay present enough, alert enough, to notice the painbody in yourself as a heavy influx of negative emotion when it becomes active. When it is recognized, it can no longer pretend to be you and live and renew itself through you.
  • It is your conscious Presence that breaks the identification with the painbody. When you don't identify with it, the painbody can no longer control your thinking and so cannot renew itself anymore by feeding on your thoughts. The painbody in most cases does not dissolve immediately, but once you have severed the link between it and your thinking, the painbody begins to lose energy. Your thinking ceases to be clouded by emotion; your present perceptions are no longer distorted by the past. The energy that was trapped in the painbody then changes into vibrational frequency and is transmuted into Presence. In this way, the painbody becomes fuel for consciousness. This is why many of the wisest, most enlightened men and women on our planet once had a heavy painbody.
  • Children are not fooled by parents who try to hide their painbody from them, who say to each other, “We mustn't fight in front of the children.” This usually means while the parents make polite conversation, the home is pervaded with negative energy. Suppressed painbodies are extremely toxic, even more so than openly active ones, and that psychic toxicity is absorbed by the children and contributes to the development of their own painbody.
  • Many people live with a tormentor in their head that continuously attacks and punishes them and drains them of vital energy. It is the cause of untold misery and unhappiness, as well as of disease. The good news is that you can free yourself from your mind. This is the only true liberation. You can take the first step right now. Start listening to the voice in your head as often as you can. Pay particular attention to any repetitive thought patterns, those old gramophone records that have been playing in your head perhaps for many years. This is what I mean by "watching the thinker," which is another way of saying: listen to the voice in your head, be there as the witnessing presence. When you listen to that voice, listen to it impartially. That is to say, do not judge. Do not judge or condemn what you hear, for doing so would mean that the same voice has come in again through the back door. You'll soon realize: there is the voice, and here I am listening to it, watching it. This I am realization, this sense of your own presence, is not a thought. It arises from beyond the mind.
    • Eckhart Tolle in A New Earth: Awakening to Your Life's Purpose, p. 17, (2005)
  • That last moment belongs to us — that agony is our triumph.
  • Interesting problem, pain. So helpful, so obnoxious.
  • At first blush, the Unborn Child Pain Awareness Act would seem to be anathema to abortion rights groups. It requires abortion providers to tell a woman whose pregnacy is 20 weeks past fertilization "there is substantial evidence" that the fetus will feel pain during the procedure -- a point hotly debated among physicians and pain specialists.
    The woman would then have to sign a form accepting or declining anesthesia for her fetus. Some medical groups interpret the language to mean that the fetus would have to have an application of anesthesia separate from the mother's, a procedure that many abortion clinics are not capable of providing.
  • It may seem to be a long way from Blake's innocent talk of love and copulation to De Sade's need to inflict pain. And yet both are the outcome of a sexual mysticism that strives to transcend the everyday world. Simone de Beauvoir said penetratingly of De Sade's work that 'he is trying to communicate an experience whose distinguishing characteristic is, nevertheless its will to remain incommunicable'. De Sade's perversion may have sprung from his dislike of his mother or of other women, but its basis is a kind of distorted religious emotion.
    • Colin Wilson in The Origins of the Sexual Impulse, p. 90 (1963)
  • It’s a big disappointment for the pro-life movement, which has embraced 20-week bans as a way of taking advantage of public discomfort over later abortion. Based on the disputed medical claim that a fetus can feel pain after 20 weeks, thirteen states have banned abortions after that point, and Republicans in Congress have introduced similar federal legislation. Had the Albuquerque referendum passed, it would have opened up new avenues for anti-abortion groups to pursue restrictions at the local level—an attractive prospect in blue states like New Mexico, where the Democratic-controlled legislature has repeatedly buried new abortion laws.

Hoyt's New Cyclopedia Of Practical Quotations

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Quotes reported in Hoyt's New Cyclopedia Of Practical Quotations (1922), p. 575-76.
  • World's use is cold, world's love is vain,
    World's cruelty is bitter bane;
    But pain is not the fruit of pain.
  • Nature knows best, and she says, roar!
  • Pain is good, I'd say, when it's incidental to Love. In 'I give up my life for my friend' it is my friend, not my death, that matters. And sometimes I needn't give up my life for him, I can live for him, and with him, and the power of the spirit is then equally manifested, I should think.
    • E. M. Forster, Selected Letters: Letter 285, to George Thomson, 1 August 1931.
  • There is purpose in pain,
    Otherwise it were devilish.
    • Owen Meredith (Lord Lytton), Lucile (1860), Part II, Canto V, Stanza 8.
  • You purchase pain with all that joy can give,
    And die of nothing but a rage to live.
  • To have pain is to have certainty; to hear about pain is to have doubt.
    • Elaine Scarry in The Body in Pain (1985)
  • The scourge of life, and death's extreme disgrace,
    The smoke of hell,—that monster callèd Paine.
  • Your pain comes upon the individual, one by one, to each man alone and no other, but my soul groans for the city, for me and you together.
  • There's a pang in all rejoicing,
    And a joy in the heart of pain;
    And the wind that saddens, the sea that gladdens,
    Are singing the selfsame strain.
  • Nothing begins, and nothing ends,
    That is not paid with moan;
    For we are born in others' pain,
    And perish in our own.
  • The mark of rank in nature is capacity for pain,
    And the anguish of the singer marks the sweetness of the strain.
  • A man of pleasure is a man of pains.
    • Edward Young, Night Thoughts (1742-1745), Night VIII, line 793.
  • When pain can't bless, heaven quits us in despair.
    • Edward Young, Night Thoughts (1742-1745), Night IX, line 500.

"Fetal pain: a systematic multidisciplinary review of the evidence" (2005)

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Lee SJ, Ralston HJ, Drey EA, Partridge JC, Rosen MA (2005). "Fetal pain: a systematic multidisciplinary review of the evidence". JAMA. 294 (8): 947–954. doi:10.1001/jama.294.8.947. PMID 16118385.

  • Evidence Synthesis Pain perception requires conscious recognition or awareness of a noxious stimulus. Neither withdrawal reflexes nor hormonal stress responses to invasive procedures prove the existence of fetal pain, because they can be elicited by nonpainful stimuli and occur without conscious cortical processing. Fetal awareness of noxious stimuli requires functional thalamocortical connections. Thalamocortical fibers begin appearing between 23 to 30 weeks’ gestational age, while electroencephalography suggests the capacity for functional pain perception in preterm neonates probably does not exist before 29 or 30 weeks. For fetal surgery, women may receive general anesthesia and/or analgesics intended for placental transfer, and parenteral opioids may be administered to the fetus under direct or sonographic visualization. In these circumstances, administration of anesthesia and analgesia serves purposes unrelated to reduction of fetal pain, including inhibition of fetal movement, prevention of fetal hormonal stress responses, and induction of uterine atony.
    Conclusions Evidence regarding the capacity for fetal pain is limited but indicates that fetal perception of pain is unlikely before the third trimester. Little or no evidence addresses the effectiveness of direct fetal anesthetic or analgesic techniques. Similarly, limited or no data exist on the safety of such techniques for pregnant women in the context of abortion. Anesthetic techniques currently used during fetal surgery are not directly applicable to abortion procedures.
  • Pain is a subjective sensory and emotional experience that requires the presence of consciousness to permit recognition of a stimulus as unpleasant. Although pain is commonly associated with physical noxious stimuli, such as when one suffers a wound, pain is fundamentally a psychological construct that may exist even in the absence of physical stimuli, as seen in phantom limb pain. The psychological nature of pain also distinguishes it from nociception, which involves physical activation of nociceptive pathways without the subjective emotional experience of pain. For example, nociception without pain exists below the level of a spinal cord lesion, where reflex withdrawal from a noxious stimulus occurs without conscious perception of pain.
    Because pain is a psychological construct with emotional content, the experience of pain is modulated by changing emotional input and may need to be learned through life experience. Regardless of whether the emotional content of pain is acquired, the psychological nature of pain presupposes the presence of functional thalamocortical circuitry required for conscious perception, as discussed below.
  • Nociception may be characterized by reflex movement in response to a noxious stimulus, without cortical involvement or conscious pain perception. Nociception involves peripheral sensory receptors whose afferent fibers synapse in the spinal cord on interneurons, which synapse on motor neurons that also reside in the spinal cord. These motor neurons trigger muscle contraction, causing limb flexion away from a stimulus.
    In contrast, pain perception requires cortical recognition of the stimulus as unpleasant. Peripheral sensory receptor afferents synapse on spinal cord neurons, the axons of which project to the thalamus, which sends afferents to the cerebral cortex, activating any number of cortical regions. Sensory receptors and spinal cord synapses required for nociception develop earlier than the thalamocortical pathways required for conscious perception of pain.
    No human studies have directly examined the development of thalamocortical circuits associated with pain perception. The developmental age at which thalamic pain fibers reach the cortex has been inferred from studies of other thalamocortical circuits, which may or may not develop at the same time as thalamic fibers mediating cortical perception of pain.
  • Another histological study of 12 specimens found that afferents from unspecified thalamic regions reached the developing prefrontal cortex in 1 preterm neonate of 27 weeks’ developmental age, concluding that thalamic fibers begin entering the cortex between 26 and 28 weeks’ developmental age (28 and 30 weeks’ gestational age). A different study found that thalamic afferents had not reached the somatosensory cortical plate by 22 weeks’ developmental age (24 weeks’ gestational age). By 24 weeks’ developmental age (26 weeks’ gestational age), the density of cortical plate synapses increased, although these were not necessarily from thalamic afferents. Based on these studies, direct thalamocortical fibers that are not specific for pain begin to emerge between 21 and 28 weeks’ developmental age (23 and 30 weeks’ gestational age).
  • Despite this developmental role, no human study has shown that synapses between subplate and cortical plate neurons convey information about pain perception from the thalamus to the developing cortex.
  • The histological presence of thalamocortical fibers is insufficient to establish capacity for pain perception. These anatomical structures must also be functional. Although no electroencephalographic “pain pattern” exists, electroencephalography may be one way of assessing general cortical function because electroencephalograms (EEGs) measure summated synaptic potentials from cortical neurons.
  • Somatosensory evoked potentials (SEPs) may also provide evidence of pain processing in the somatosensory cortex, although they are not used clinically to test pain pathways. SEPs test the dorsal column tract of the spinal cord, which transmits visceral pain sensation to the somatosensory cortex via the thalamus. SEPs with distinct and constant N1 components of normal peak latency are present at 29 weeks’ PCA, indicating that thalamic connections with the somatosensory cortex are functional at that time.
  • Although widely used to assess pain in neonates, withdrawal reflexes and facial movements do not necessarily represent conscious perception of pain. Full-term neonates exhibit a “cutaneous withdrawal reflex” that is activated at a threshold much lower than that which would produce discomfort in a child or adult. This threshold increases with PCA, suggesting that the capacity of the neonate to distinguish between noxious and nonnoxious stimuli is maturing. Furthermore, flexion withdrawal from tactile stimuli is a noncortical spinal reflex exhibited by infants with anencephaly and by individuals in a persistent vegetative state who lack cortical function.
    Behavioral studies have also identified a distinct set of neonatal facial movements present during invasive procedures such as heel lancing but absent during noninvasive procedures. These facial movements, which are similar to those of adults experiencing pain, were evident in neonates at 28 to 30 weeks’ PCA but not at 25 to 27 weeks’ PCA. Facial movements may not necessarily be cortically controlled. One study found no difference in facial activity during heel lancing of neonates with and without significant cortical injury, suggesting that facial activity even around 32 weeks’ PCA may not represent conscious perception of pain.
  • Hemodynamic and neuroendocrine changes in fetuses undergoing stressful procedures have also been used to infer pain perception. As early as 16 weeks’ gestational age, fetal cerebral blood flow increases during venipuncture and transfusions that access the fetal hepatic vein through the innervated fetal abdominal wall but not during venipuncture and transfusions involving the noninnervated umbilical cord. Increased cerebral blood flow is not necessarily indicative of pain, as this response is thought to constitute a “brain sparing” mechanism associated with hypoxia and intrauterine growth restriction.
  • Other investigators measured increases in fetal plasma concentrations of cortisol, β-endorphin, and noradrenaline associated with intrauterine needling procedures, finding that increases during blood sampling from the hepatic vein were greater than those during sampling from the umbilical cord. However, these neuroendocrine responses do not constitute evidence of fetal pain, because the autonomic nervous system and hypothalamic-pituitary-adrenal axis mediate them without conscious cortical processing. Additionally, these responses are not specific for painful stimuli. Plasma noradrenaline concentrations may increase after umbilical cord transfusion, and plasma β-endorphin concentrations may increase after repeated cordocenteses. Plasma cortisol and β-endorphin concentrations increase during innocuous activities such as exercise. Moreover, in adults, neuroendocrine stress responses may persist despite well-controlled postoperative pain.
    Vital signs also have been used to assess neonatal pain.
  • Anesthetics and analgesics are commonly used to alleviate pain and discomfort. Despite ongoing debate regarding fetal capacity for pain, fetal anesthesia and analgesia are still warranted for surgical procedures undertaken to promote fetal health. When long-term fetal well-being is a central consideration, evidence of fetal pain is unnecessary to justify fetal anesthesia and analgesia because they serve other purposes unrelated to pain reduction, including (1) inhibiting fetal movement during a procedure; (2) achieving uterine atony to improve surgical access to the fetus and to prevent contractions and placental separation; (3) preventing hormonal stress responses associated with poor surgical outcomes in neonates; and (4) preventing possible adverse effects on long-term neurodevelopment and behavioral responses to pain.
    These objectives are not applicable to abortions. Instead, beneficence toward the fetus represents the chief justification for using fetal anesthesia or analgesia during abortion—to relieve suffering if fetal pain exists.
  • In contrast to fetal surgery requiring regional or general anesthesia, minimally invasive fetal procedures do not involve maternal laparotomy or hysterotomy and instead use needles or endoscopy to access the fetus. For the sake of reducing pain, the increased risks of general anesthesia are unjustified for these procedures; adults typically undergo similar procedures with no analgesia or only local analgesia.
  • Pain is an emotional and psychological experience that requires conscious recognition of a noxious stimulus. Consequently, the capacity for conscious perception of pain can arise only after thalamocortical pathways begin to function, which may occur in the third trimester around 29 to 30 weeks’ gestational age, based on the limited data available. Small-scale histological studies of human fetuses have found that thalamocortical fibers begin to form between 23 and 30 weeks’ gestational age, but these studies did not specifically examine thalamocortical pathways active in pain perception.
    While the presence of thalamocortical fibers is necessary for pain perception, their mere presence is insufficient—this pathway must also be functional. It has been proposed that transient, functional thalamocortical circuits may form via subplate neurons around midgestation, but no human study has demonstrated this early functionality. Instead, constant SEPs appear at 29 weeks’ PCA, and EEG patterns denoting wakefulness appear around 30 weeks’ PCA. Both of these tests of cortical function suggest that conscious perception of pain does not begin before the third trimester. Cutaneous withdrawal reflexes and hormonal stress responses present earlier in development are not explicit or sufficient evidence of pain perception because they are not specific to noxious stimuli and are not cortically mediated.
  • In the context of abortion, fetal analgesia would be used solely for beneficence toward the fetus, assuming fetal pain exists. This interest must be considered in concert with maternal safety and fetal effectiveness of any proposed anesthetic or analgesic technique. For instance, general anesthesia increases abortion morbidity and mortality for women and substantially increases the cost of abortion. Although placental transfer of many opioids and sedative-hypnotics has been determined, the maternal dose required for fetal analgesia is unknown, as is the safety for women at such doses. Furthermore, no established protocols exist for administering anesthesia or analgesia directly to the fetus for minimally invasive fetal procedures or abortions. Experimental techniques, such as administration of fentanyl directly to the fetus and intra-amniotic injection of sufentanil in pregnant ewes, have not been shown to decrease fetal pain and are of unknown safety in humans.
  • Because pain perception probably does not function before the third trimester, discussions of fetal pain for abortions performed before the end of the second trimester should be noncompulsory. Fetal anesthesia or analgesia should not be recommended or routinely offered for abortion because current experimental techniques provide unknown fetal benefit and may increase risks for the woman. Instead, further research should focus on when pain-related thalamocortical pathways become functional in humans. If the fetus can feel pain, additional research may lead to effective fetal anesthesia or analgesia techniques that are also safe for women.
  • Merker’s much-discussed article was accompanied by more than two dozen commentaries by prominent researchers. Many noted that if Merker is correct, it could alter our understanding of how normal brains work and could change our treatment of those who are now believed to be insensible to pain because of an absent or damaged cortex. For example, the decision to end the life of a patient in a persistent vegetative state might be carried out with a fast-acting drug, suggested Marshall Devor, a biologist at the Center for Research on Pain at Hebrew University in Jerusalem. Devor wrote that such a course would be more humane than the weeks of potentially painful starvation that follows the disconnection of a feeding tube (though as a form of active euthanasia it would be illegal in the United States and most other countries). The possibility of consciousness without a cortex may also influence our opinion of what a fetus can feel. Like the subplate zone, the brain stem is active in the fetus far earlier than the cerebral cortex is, and if it can support consciousness, it can support the experience of pain. While Mark Rosen is skeptical, Anand praises Merker’s work as a “missing link” that could complete the case for fetal pain.

"The importance of 'awareness' for understanding fetal pain" (2005)

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Mellor, D.J.; Diesch, T.J.; Gunn, A.J.; Bennet, L. (2005). "The importance of 'awareness' for understanding fetal pain". Brain Research Reviews. 49 (3): 455–71. doi:10.1016/j.brainresrev.2005.01.006. PMID 16269314. S2CID 9833426.

  • Our understanding of when the fetus can experience pain has been largely shaped by neuroanatomy. However, completion of the cortical nociceptive connections just after mid-gestation is only one part of the story. In addition to critically reviewing evidence for whether the fetus is ever awake or aware, and thus able to truly experience pain, we examine the role of endogenous neuro-inhibitors, such as adenosine and pregnanolone, produced within the feto-placental unit that contribute to fetal sleep states, and thus mediate suppression of fetal awareness. The uncritical view that the nature of presumed fetal pain perception can be assessed by reference to the prematurely born infant is challenged. Rigorously controlled studies of invasive procedures and analgesia in the fetus are required to clarify the impact of fetal nociception on postnatal pain sensitivity and neural development, and the potential benefits or harm of using analgesia in this unique setting.
  • Whether the fetus can truly experience pain, at least in some way analogous to how adults emotionally understand pain, has been debated extensively over recent years and is of importance given continuing advances in fetal surgical and diagnostic procedures. This question has considerable implications for the management of invasive fetal procedures, particularly as fetal analgesic and anaesthetic treatment is complex and not without risk for the fetus. Prevention and treatment of pain are basic human rights, regardless of age, and if fetal interventions are to progress, then a greater understanding of nociception and stress responses is required.
    The timing of the neuroanatomical maturation of the nociceptive system is now well understood, and the final critical cortico-thalamic connections appear to be present by 24–28 weeks of gestation. This suggests that the fetus could potentially be able to feel pain by the third trimester, at least in a rudimentary fashion. This concept is said to be supported by studies which show that nociceptive stimuli elicit physiological stress-like responses in the human fetus in utero.
    However, physiological processing of a nociceptive stimulus and perceiving a nociceptive stimulus as painful are not the same. There are both a physiological and an emotional or cognitive aspect to pain perception, and indeed a significant element of learning [56]. Certainly, processing can be independent of perception, as is demonstrated during surgery under general anesthesia, for example, where nociceptive stimuli can still elicit subcortically mediated physiological stress responses despite unconsciousness. Thus, to emotionally experience pain, we must be cognitively aware of the stimulus (a cortical process), and this in turn requires that we must be conscious.
    The key question then is not about the anatomic completion or functionality of nociceptive pathways in utero, but whether the fetus is ever conscious and thus aware. In general, discussion of fetal pain perception tends to treat the fetus as an unborn newborn; i.e., that responses of the newborn represent an adequate surrogate for the fetus. The assumption is thus made that if the newborn (including the preterm newborn) can experience wakefulness (and therefore consciousness), and apparently feels pain, then so too must the age-equivalent fetus. Furthermore, evidence for fetal wakefulness (and again therefore consciousness) has been based on how certain fetal responses “resemble” newborn sleep–wake behaviors, rather than a true determination of fetal wakefulness per se. Given the complexities of studying the fetus, extrapolation from or to the newborn state is understandable. Systematic studies of fetal neurological function suggest, however, that there are major differences in the in utero environment and fetal neural state that make it likely that this assumption is substantially incorrect. This has important implications for our understanding of fetal pain perception.
    The current review critically evaluates the hypothesis that unlike the newborn, the fetus is actively maintained asleep (and unconscious) throughout gestation and cannot be woken by nociceptive stimuli. The evidence is examined with reference to fetal sleep–wake states, the role of cortico-thalamic gating in cortical arousal during sleep, and the unique contribution that certain inhibitory neuromodulators make in utero to cortical suppression. Finally, we briefly discuss the validity of the hypothesis that suggests that the nociceptive input may have long-lasting deleterious effects regardless of whether the fetus is asleep or not.
  • The processing of nociceptive stimuli requires peripheral sensory receptors, afferent and efferent sensory and motor pathways, and subcortical and cortical neural integration of the related impulse traffic. The development of nociceptive pathways has been extensively reviewed by others and is not the subject of this review. In brief, however, it is generally agreed that an integrated pathway exists by 24–28 weeks of gestation and that
  • The conclusion suggested in the section above is further strengthened by consideration of the increasing body of evidence which shows that there are several suppressors in utero which act to inhibit neural activity in the fetus to a far greater degree than is seen postnatally in the infant. The uterus plays a key role in providing the chemical and physical factors that together help to keep the fetus continuously asleep. We propose that this is achieved, among other things, through the combined
  • Here we consider one final issue: whether nociceptive inputs may have deleterious consequences even if the “endogenously anesthetized” fetus does not consciously perceive pain at the time of stimulation. Can exposure to noxious stimuli initiate a cascade of events that sensitize the nervous system, or can repeated pain exposure in preterm infants contribute to attention, learning, and behavior problems later in life? It is critical to appreciate that not only is most of
  • We have considered whether the fetus, once its nociceptive pathways are complete, can feel pain in utero in a psychological manner akin to adult pain experience, and whether regardless of this the physiological responses to nociceptive input may lead to altered behavior later in life. We conclude that there is currently no strong evidence to suggest that the fetus is ever awake, even transiently; rather, it is actively kept asleep (and unconscious) by a variety of endogenous inhibitory factors.

"The First Ache" (February 10, 2008)

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Paul, Annie (10 February 2008). "The First Ache". The New York Times Magazine.

  • Twenty-five years ago, when Kanwaljeet Anand was a medical resident in a neonatal intensive care unit, his tiny patients, many of them preterm infants, were often wheeled out of the ward and into an operating room. He soon learned what to expect on their return. The babies came back in terrible shape: their skin was gray, their breathing shallow, their pulses weak. Anand spent hours stabilizing their vital signs, increasing their oxygen supply and administering insulin to balance their blood sugar.
    “What’s going on in there to make these babies so stressed?” Anand wondered. Breaking with hospital practice, he wrangled permission to follow his patients into the O.R. “That’s when I discovered that the babies were not getting anesthesia,” he recalled recently. Infants undergoing major surgery were receiving only a paralytic to keep them still. Anand’s encounter with this practice occurred at John Radcliffe Hospital in Oxford, England, but it was common almost everywhere. Doctors were convinced that newborns’ nervous systems were too immature to sense pain, and that the dangers of anesthesia exceeded any potential benefits.
    Anand resolved to find out if this was true. In a series of clinical trials, he demonstrated that operations performed under minimal or no anesthesia produced a “massive stress response” in newborn babies, releasing a flood of fight-or-flight hormones like adrenaline and cortisol. Potent anesthesia, he found, could significantly reduce this reaction. Babies who were put under during an operation had lower stress-hormone levels, more stable breathing and blood-sugar readings and fewer postoperative complications. Anesthesia even made them more likely to survive. Anand showed that when pain relief was provided during and after heart operations on newborns, the mortality rate dropped from around 25 percent to less than 10 percent. These were extraordinary results, and they helped change the way medicine is practiced. Today, adequate pain relief for even the youngest infants is the standard of care, and the treatment that so concerned Anand two decades ago would now be considered a violation of medical ethics.
    But Anand was not through with making observations. As NICU technology improved, the preterm infants he cared for grew younger and younger — with gestational ages of 24 weeks, 23, 22 — and he noticed that even the most premature babies grimaced when pricked by a needle. “So I said to myself, Could it be that this pain system is developed and functional before the baby is born?”
  • Whether the fetus feels pain is a question that matters to the doctor wielding the scalpel.
    And it matters, of course, for the practice of abortion. Over the past four years, anti-abortion groups have turned fetal pain into a new front in their battle to restrict or ban abortion. Anti-abortion politicians have drafted laws requiring doctors to tell patients seeking abortions that a fetus can feel pain and to offer the fetus anesthesia; such legislation has already passed in five states. Anand says he does not oppose abortion in all circumstances but says decisions should be made on a case-by-case basis. Nonetheless, much of the activists’ and lawmakers’ most powerful rhetoric on fetal pain is borrowed from Anand himself.
  • Even as some research suggests that fetuses can feel pain as preterm babies do, other evidence indicates that they are anatomically, biochemically and psychologically distinct from babies in ways that make the experience of pain unlikely. The truth about fetal pain can seem as murky as an image on an ultrasound screen, a glimpse of a creature at once recognizably human and uncomfortably strange.
  • IF THE NOTION that newborns are incapable of feeling pain was once widespread among doctors, a comparable assumption about fetuses was even more entrenched. Nicholas Fisk is a fetal-medicine specialist and director of the University of Queensland Center for Clinical Research in Australia. For years, he says, “I would be doing a procedure to a fetus, and the mother would ask me, ‘Does my baby feel pain?’ The traditional, knee-jerk reaction was, ‘No, of course not.’” But research in Fisk’s laboratory (then at Imperial College in London) was making him uneasy about that answer. It showed that fetuses as young as 18 weeks react to an invasive procedure with a spike in stress hormones and a shunting of blood flow toward the brain — a strategy, also seen in infants and adults, to protect a vital organ from threat. Then Fisk carried out a study that closely resembled Anand’s pioneering research, using fetuses rather than newborns as his subjects. He selected 45 fetuses that required a potentially painful blood transfusion, giving one-third of them an injection of the potent painkiller fentanyl. As with Anand’s experiments, the results were striking: in fetuses that received the analgesic, the production of stress hormones was halved, and the pattern of blood flow remained normal.
    Fisk says he believes that his findings provide suggestive evidence of fetal pain — perhaps the best evidence we’ll get. Pain, he notes, is a subjective phenomenon; in adults and older children, doctors measure it by asking patients to describe what they feel. (“On a scale of 0 to 10, how would you rate your current level of pain?”) To be certain that his fetal patients feel pain, Fisk says, “I would need one of them to come up to me at the age of 6 or 7 and say, ‘Excuse me, Doctor, that bloody hurt, what you did to me!’ ” In the absence of such first-person testimony, he concludes, it’s “better to err on the safe side” and assume that the fetus can feel pain starting around 20 to 24 weeks.
  • Mark Rosen was the anesthesiologist at the very first open fetal operation, performed in 1981 at the University of California, San Francisco, Medical Center, and the fetal anesthesia protocols he pioneered are now followed by his peers all over the world. Indeed, Rosen may have done more to prevent fetal pain than anyone else alive — except that he doesn’t believe that fetal pain exists. Research has persuaded him that before a point relatively late in pregnancy, the fetus is unable to perceive pain.
    Rosen provides anesthesia for a number of other important reasons, he explains, including rendering the pregnant woman unconscious and preventing her uterus from contracting and setting off dangerous bleeding or early labor. Another purpose of anesthesia is to immobilize the fetus during surgery, and indeed, the drugs Rosen supplies to the pregnant woman do cross the placenta to reach the fetus. Relief of fetal pain, however, is not among his objectives. “I have every reason to want to believe that the fetus feels pain, that I’ve been treating pain all these years,” says Rosen, who is intense and a bit prickly. “But if you look at the evidence, it’s hard to conclude that that’s true.”
  • Rosen’s own hard look at the evidence came a few years ago, when he and a handful of other doctors at U.C.S.F. pulled together more than 2,000 articles from medical journals, weighing the accumulated evidence for and against fetal pain. They published the results in The Journal of the American Medical Association in 2005. “Pain perception probably does not function before the third trimester,” concluded Rosen, the review’s senior author. The capacity to feel pain, he proposed, emerges around 29 to 30 weeks gestational age, or about two and a half months before a full-term baby is born. Before that time, he asserted, the fetus’s higher pain pathways are not yet fully developed and functional.
    What about a fetus that draws back at the touch of a scalpel? Rosen says that, at least early on, this movement is a reflex, like a leg that jerks when tapped by a doctor’s rubber mallet.
  • Likewise, the release of stress hormones doesn’t necessarily indicate the experience of pain; stress hormones are also elevated, for example, in the bodies of brain-dead patients during organ harvesting. In order for pain to be felt, he maintains, the pain signal must be able to travel from receptors located all over the body, to the spinal cord, up through the brain’s thalamus and finally into the cerebral cortex. The last leap to the cortex is crucial, because this wrinkly top layer of the brain is believed to be the organ of consciousness, the generator of awareness of ourselves and things not ourselves (like a surgeon’s knife). Before nerve fibers extending from the thalamus have penetrated the cortex — connections that are not made until the beginning of the third trimester — there can be no consciousness and therefore no experience of pain.
    Sunny Anand reacted strongly, even angrily, to the article’s conclusions. Rosen and his colleagues have “stuck their hands into a hornet’s nest,” Anand said at the time. “This is going to inflame a lot of scientists who are very, very concerned and are far more knowledgeable in this area than the authors appear to be. This is not the last word — definitely not.” Anand acknowledges that the cerebral cortex is not fully developed in the fetus until late in gestation. What is up and running, he points out, is a structure called the subplate zone, which some scientists believe may be capable of processing pain signals. A kind of holding station for developing nerve cells, which eventually melds into the mature brain, the subplate zone becomes operational at about 17 weeks. The fetus’s undeveloped state, in other words, may not preclude it from feeling pain. In fact, its immature physiology may well make it more sensitive to pain, not less: the body’s mechanisms for inhibiting pain and making it more bearable do not become active until after birth.
  • Merker’s much-discussed article was accompanied by more than two dozen commentaries by prominent researchers. Many noted that if Merker is correct, it could alter our understanding of how normal brains work and could change our treatment of those who are now believed to be insensible to pain because of an absent or damaged cortex. For example, the decision to end the life of a patient in a persistent vegetative state might be carried out with a fast-acting drug, suggested Marshall Devor, a biologist at the Center for Research on Pain at Hebrew University in Jerusalem. Devor wrote that such a course would be more humane than the weeks of potentially painful starvation that follows the disconnection of a feeding tube (though as a form of active euthanasia it would be illegal in the United States and most other countries). The possibility of consciousness without a cortex may also influence our opinion of what a fetus can feel. Like the subplate zone, the brain stem is active in the fetus far earlier than the cerebral cortex is, and if it can support consciousness, it can support the experience of pain. While Mark Rosen is skeptical, Anand praises Merker’s work as a “missing link” that could complete the case for fetal pain.
  • Even birth may not inaugurate the ability to feel pain, according to Stuart Derbyshire, a psychologist at the University of Birmingham in Britain. Derbyshire is a prolific commentator on the subject and an energetic provocateur. In milder moods, he has described the notion of fetal pain as a “fallacy”; when goaded by his critics’ “lazy” thinking, he has pronounced it a “moral blunder” and “a shoddy, sentimental argument.”
    For all his vehemence in print, Derbyshire is affable in conversation, explaining that his laboratory research on the neurological basis of pain in adults led him to the matter of what fetuses feel: “For me, it’s an interesting test case of what we know about pain. It’s a great application of theory, basically.” The theory, in this case, is that the experience of pain has to be learned — and the fetus, lacking language or interactions with caregivers, has no chance of learning it. In place of distinct emotions, it experiences a blur of sensations, a condition Derbyshire has likened to looking at “a vast TV screen with all of the world’s information upon it from a distance of one inch; a great buzzing mass of meaningless information,” he writes.
  • “Before a symbolic system such as language, an individual will not know that something in front of them is large or small, hot or cold, red or green” — or, Derbyshire argues, painful or pleasant.
    He finds “outrageous” the suggestion that the fetus feels anything like the pain that an older child or an adult experiences. “A fetus is biologically human, of course,” he says. “It isn’t a cow. But it’s not yet psychologically human.” That is a status not bestowed at conception but earned with each connection made and word spoken. Following this logic to its conclusion, Derbyshire has declared that babies cannot feel pain until they are 1 year old. His claim has become notorious in pain-research circles, and even Derbyshire says he thinks he may have overstepped. “I sometimes regret that I pushed it out quite that far,” he concedes. “But really, who knows when the light finally switches on?”
  • IN FACT, “THERE may not be a single moment when consciousness, or the potential to experience pain, is turned on,” Nicholas Fisk wrote with Vivette Glover, a colleague at Imperial College, in a volume on early pain edited by Anand. “It may come on gradually, like a dimmer switch.” It appears that this slow dawning begins in the womb and continues even after birth. So where do we draw the line? When does a release of stress hormones turn into a grimace of genuine pain?
  • Recent research provides a potentially urgent reason to ask this question. It shows that pain may leave a lasting, even lifelong, imprint on the developing nervous system. For adults, pain is usually a passing sensation, to be waited out or medicated away. Infants, and perhaps fetuses, may do something different with pain: some research suggests they take it into their bodies, making it part of their fast-branching neural networks, part of their flesh and blood.
    Anna Taddio, a pain specialist at the Hospital for Sick Children in Toronto, noticed more than a decade ago that the male infants she treated seemed more sensitive to pain than their female counterparts. This discrepancy, she reasoned, could be due to sex hormones, to anatomical differences — or to a painful event experienced by many boys: circumcision. In a study of 87 baby boys, Taddio found that those who had been circumcised soon after birth reacted more strongly and cried for longer than uncircumcised boys when they received a vaccination shot four to six months later. Among the circumcised boys, those who had received an analgesic cream at the time of the surgery cried less while getting the immunization than those circumcised without pain relief.
    Taddio concluded that a single painful event could produce effects lasting for months, and perhaps much longer. “When we do something to a baby that is not an expected part of its normal development, especially at a very early stage, we may actually change the way the nervous system is wired,” she says. Early encounters with pain may alter the threshold at which pain is felt later on, making a child hypersensitive to pain — or, alternatively, dangerously indifferent to it. Lasting effects might also include emotional and behavioral problems like anxiety and depression, even learning disabilities (though these findings are far more tentative).
    Do such long-term effects apply to fetuses? They may well, especially since pain experienced in the womb would be even more anomalous than pain encountered soon after birth. Moreover, the ability to feel pain may not need to be present in order for “noxious stimulation” — like a surgeon’s incision — to do harm to the fetal nervous system. This possibility has led some to venture an early end to the debate over fetal pain. Marc Van de Velde, an anesthesiologist and pain expert at University Hospitals Gasthuisberg in Leuven, Belgium, says: “We know that the fetus experiences a stress reaction, and we know that this stress reaction may have long-term consequences — so we need to treat the reaction as well as we can. Whether or not we call it pain is, to me, irrelevant.”
  • BUT THE QUESTION of fetal pain is not irrelevant when applied to abortion. On April 4, 2004, Sunny Anand took the stand in a courtroom in Lincoln, Neb., to testify as an expert witness in the case of Carhart v. Ashcroft. This was one of three federal trials held to determine the constitutionality of the ban on a procedure called intact dilation and extraction by doctors and partial-birth abortion by anti-abortion groups. Anand was asked whether a fetus would feel pain during such a procedure. “If the fetus is beyond 20 weeks of gestation, I would assume that there will be pain caused to the fetus,” he said. “And I believe it will be severe and excruciating pain.”
    After listening to Anand’s testimony and that of doctors opposing the law, Judge Richard G. Kopf declared in his opinion that it was impossible for him to decide whether a “fetus suffers pain as humans suffer pain.” He ruled the law unconstitutional on other grounds. But the ban was ultimately upheld by the U.S. Supreme Court, and Anand’s statements, which he repeated at the two other trials, helped clear the way for legislation aimed specifically at fetal pain. The following month, Sam Brownback, Republican of Kansas, presented to the Senate the Unborn Child Pain Awareness Act, requiring doctors to tell women seeking abortions at 20 weeks or later that their fetuses can feel pain and to offer anesthesia “administered directly to the pain-capable unborn child.” The bill did not pass, but Brownback continues to introduce it each year. Anand’s testimony also inspired efforts at the state level. Over the past two years, similar bills have been introduced in 25 states, and in 5 — Arkansas, Georgia, Louisiana, Minnesota and Oklahoma — they have become law. In addition, state-issued abortion-counseling materials in Alaska, South Dakota and Texas now make mention of fetal pain.
  • In the push to pass fetal-pain legislation, Anand’s name has been invoked at every turn; he has become a favorite expert of the anti-abortion movement precisely because of his credentials. “This Oxford- and Harvard-trained neonatal pediatrician had some jarring testimony about the subject of fetal pain,” announced the Republican congressman Mike Pence to the House of Representatives in 2004, “and it is truly made more astonishing when one considers the fact that Dr. Anand is not a stereotypical Bible-thumping pro-lifer.” Anand maintains that doctors performing abortions at 20 weeks or later should take steps to prevent or relieve fetal pain. But it is clear that many of the anti-abortion activists who quote him have something more sweeping in mind: changing perceptions of the fetus. In several states, for example, information about fetal pain is provided to all women seeking abortions, including those whose fetuses are so immature that there is no evidence of the existence of even a stress response. “By personifying the fetus, they’re trying to steer the woman’s decision away from abortion,” says Elizabeth Nash, a public-policy associate at the Guttmacher Institute, a reproductive-rights group.
  • In his speeches about fetal pain, Senator Brownback often asks why a fetus undergoing surgery receives anesthesia but not a fetus “who is undergoing the life-terminating surgery of an abortion.” Mark Rosen rejects the analogy. “Fetal surgery is a different circumstance than abortion,” he says, pointing out that none of the objectives of anesthesia for fetal surgery — relaxing the uterus, for example — apply to the termination of pregnancy. That includes an objective identified just recently: preventing possible long-term damage. For the fetus that is to be aborted, there is no long term. And if there is no pain, as Rosen maintains, then there is no cause to put the woman’s health at risk.
  • In their use of pain to make the fetus seem more fully human, anti-abortion forces draw on a deep tradition. Pain has long played a special role in how society determines who is like us or not like us (“us” being those with the power to make and enforce such distinctions). The capacity to feel pain has often been put forth as proof of a common humanity. Think of Shylock’s monologue in “The Merchant of Venice”: Are not Jews “hurt with the same weapons” as Christians, he demands. “If you prick us, do we not bleed?” Likewise, a presumed insensitivity to pain has been used to exclude some from humanity’s privileges and protections. Many 19th-century doctors believed blacks were indifferent to pain and performed surgery on them without even that era’s rudimentary anesthesia. Over time, the charmed circle of those considered alive to pain, and therefore fully human, has widened to include members of other religions and races, the poor, the criminal, the mentally ill — and, thanks to the work of Sunny Anand and others, the very young. Should the circle enlarge once more, to admit those not yet born? Should fetuses be added to what Martin Pernick, a historian of the use of anesthesia, has called “the great chain of feeling”? Anand maintains that they should.
  • When it comes to the way adults feel pain, science has borne out the optimistic belief that we are all the same under the skin. As research is now revealing, the same may not be true for fetuses; even Anand calls the fetus “a unique organism.” Exhibiting his flair for the startling but apt expression, Stuart Derbyshire warns against “anthropomorphizing” the fetus, investing it with human qualities it has yet to develop. To do so, he suggests, would subtract some measure of our own humanity. And to concern ourselves only with the welfare of the fetus is to neglect the humanity of the pregnant woman, Mark Rosen notes. When considering whether to provide fetal anesthesia during an abortion, he says, it’s not “erring on the safe side” to endanger a woman’s health in order to prevent fetal pain that may not exist.
    Indeed, the question remains just how far we would take the notion that the fetus is entitled to protection from pain. Would we be willing, for example, to supply a continuous flow of drugs to a fetus that is found to have a painful medical condition? For that matter, what about the pain of being born? Two years ago, a Swiftian satire of the Unborn Child Pain Awareness Act appeared on the progressive Web site AlterNet.org. Written by Lynn Paltrow, the executive director of the National Advocates for Pregnant Women, it urged the bill’s authors to extend its provisions to those fetuses “subjected to repeated, violent maternal uterine contraction and then forced through the unimaginably narrow vaginal canal.”

"Fetal Awareness"

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"Fetal Awareness". Royal College of Obstetricians and Gynaecologists.

  • Following concerns generated by the debate on fetal awareness and, particularly, the controversy around whether the fetus could feel pain, the RCOG published, in October 1997, a working party report.1 A guiding principle in that report was concern that the fetus should be protected from any potentially harmful or painful procedure but, at the same time, the assessment of the capacity to be harmed should be based on established scientific evidence. A major and important conclusion of the report was that the human fetus did not have the necessary structural integration of the nervous system to experience awareness or pain before 26 weeks of gestation. In addition, the report recommended that those carrying out diagnostic or therapeutic procedures on the fetus in utero at or after 24 weeks should consider the need for fetal analgesia.
    • p.viii
  • [B]ecause of possible risks and difficulties in administration, fetal analgesia should not be employed where the only consideration is concern about fetal awareness or pain. Similarly, there appeared to be no clear benefit in considering the need for fetal analgesia prior to termination of pregnancy, even after 24 weeks, in cases of fetal abnormality. However, this did not obviate the need to consider feticide in these circumstances and, in this respect, further recommendations of relevance are included in the parallel report on Termination of Pregnancy for Fetal Abnormality.
    • p.viii
  • Following concerns generated by the debate on fetal awareness and, particularly, the controversy around whether the fetus could feel pain, the RCOG published, in October 1997, a working party report. A guiding principle in that report was concern that the fetus should be protected from any potentially harmful or painful procedure but, at the same time, the assessment of the capacity to be harmed should be based on established scientific evidence. A major and important conclusion of the report was that the human fetus did not have the necessary structural integration of the nervous system to experience awareness or pain before 26 weeks of gestation. In addition, the report recommended that those carrying out diagnostic or therapeutic procedures on the fetus in utero at or after 24 weeks should consider the need for fetal analgesia.
    This guidance was welcomed by the clinical and scientific communities, although, in recent years, the report has from time to time come under criticism in some quarters for being out of date and perhaps not having assessed all the known scientific evidence. This criticism has been most evident in discussing the age of viability (at present taken as 24 weeks of gestation in the UK) and the upper gestational limit in the context of induced abortion. The House of Commons Science and Technology Committee, in its report on Scientific Developments Relating to the Abortion Act 1967 (published in October 2007), made a number of important conclusions and recommendations, including some of direct relevance to this issue: ‘We conclude that, while the evidence suggests that foetuses have physiological reactions to noxious stimuli, it does not indicate that pain is consciously felt, especially not below the current upper gestational limit of abortion. We further conclude that these factors may be relevant to clinical practice but do not appear to be relevant to the question of abortion’.
    A minority report, however, recorded in the minutes of the Committee on 29 October 2007 said, ‘We are deeply concerned that the RCOG failed to give full information to the House of Commons Select Committee...since 1997 the RCOG has consistently denied that foetuses can feel pain earlier than 26 weeks, without acknowledging that amongst experts in this field there is no consensus. Professor Anand is a world authority in the management of neonatal pain and has put forward a cogent argument suggesting that the RCOG position is based on a number of false or uncertain presuppositions’.
    In the Government response to the House of Commons report (released November 2007) the Minister of State for Health welcomed the report and its conclusions and recommendations but importantly also indicated that ‘we note the Committee’s findings and are in agreement that the consensus of scientific evidence with regard to fetal pain at gestations below 26 weeks and we will be commissioning the College to review their 1997 working party report into fetal pain which will re-examine the latest evidence, much of which has been considered by the Committee, and any new research currently underway’.
    • 1. Introduction, p.1
  • We begin by considering the scientific evidence for the presence of specific anatomical and physiological connections in the brain that are responsible for signalling noxious events to the central nervous system. Noxious stimuli are those that damage the tissues of the body or threaten to do so, such as surgical incision or physical trauma of the skin. In this context, we define pain as ‘the unpleasant sensory or emotional response to such tissue damage’ and trace the development of those responses through fetal development. We follow the path of the signals produced by tissue damage at sensory detectors in the skin and other organs, through to sensory circuits in the spinal cord, brainstem and thalamus and finally to the cerebral cortex, the site of higher level sensory processing. At each stage, we consider the scientific evidence for functional development and how this evidence may be interpreted. This section includes details derived from over 50 papers identified as relevant. Most were published since the last Working Party report1 but this current report also considers the older material included in the previous report.
    In addition to understanding the anatomical and physiological connections, it is also important to consider the psychological aspects of pain. Broadly accepted definitions of pain refer to pain as a subjective experience involving cognition, sensation and affective processes. These psychological concepts are inevitably harder to address in a fetus but should not be ignored.
    • 2. Neurobiological developments relevant to pain, p.3
  • The neural regions and pathways that are responsible for pain experience remain under debate but it is generally accepted that pain from physical trauma requires an intact pathway from the periphery, through the spinal cord, into the thalamus and on to regions of the cerebral cortex including the primary sensory cortex (S1), the insular cortex and the anterior cingulated cortex. Fetal pain is not possible before these necessary neural pathways and structures (figure 1) have developed.
    • p.3
  • For the fetus to respond to surgical damage, receptors in the affected tissue, such as skin and muscle, must signal the noxious stimulus or damage to the central nervous system. Nociceptors are sensory nerve terminals found in the skin and internal organs that convert tissue damage into electrical signals. The pattern and strength of these nociceptor signals is the first determining step in generating pain. If nociceptor activity is prevented, such as following local anaesthesia, then pain is blocked. Deep tissue damage, for example, that cuts through nerve bundles causes a brief burst of electrical activity in some of the cut nerve endings known as an injury discharge. The injured tissue, however, is now isolated from the central nervous system and, within a few minutes, the isolated tissue becomes ‘numb’ and pain free. Similarly, rare genetic defects that prevent all nociceptive signals result in a complete inability to sense pain.
    Anatomical studies of human fetal skin shows the presence of nerve terminals and fibres deep in the skin from 6 weeks of gestational age. These terminals are not nociceptors and are specialised for the processing of non-damaging sensations such as touch, vibration and temperature, rather than pain. From 10 weeks, nerve terminals become more numerous and extend towards the outer surface of the skin. The terminals closer to the surface are likely to be immature nociceptors, necessary for pain experience following tissue damage, but they are not unequivocally present until 17 weeks. In other mammals, newly formed fetal nociceptors are able to signal tissue damage but the intensity of their signals is weaker than in adults. The internal organs develop nerve terminals later than the skin, beginning to appear from 13 weeks and then increasing and spreading with age, so that the pancreas, for example, is innervated by 20 weeks.
    • pp.3-4
  • Specialised nerve terminals, nociceptors, are likely to detect surgical tissue damage from early in fetal life (around 10 weeks for the skin and 13 weeks for the internal organs). These nociceptors gradually mature over the next 6–8 weeks and the strength of their signals increases over fetal life. The presence of nociceptors is necessary for perception of acute surgical pain and so pain is clearly not possible before the nociceptors first appear at 10 weeks. The presence of nociceptors alone, however, is not a sufficient condition for pain experience. The electrical activity that is generated at nociceptor terminals by tissue damage must also be conducted along nerve fibres from the skin and into the spinal cord and brain. It is only when the brain receives information about the damage that the fetus can have any potential of awareness of it.
    • p.5
  • Before any information about a noxious or tissue damaging stimulus can reach the brain, it has to be transmitted through the spinal cord (for the body) or the brainstem (for the head and neck). This transmission requires the growth of nerve fibres from the skin to the spinal cord or brainstem and then further growth of nerve fibres along the spinal cord or brainstem and into the brain. Staining of postmortem tissue reveals that nerve fibres grow into the fetal spinal cord from 8 weeks. These fibres, however, are specialised for the control of movement and some aspects of touching or prodding the body or positioning a limb.
    The growth of nerve fibres connecting nociceptive terminals to the spinal cord lags behind that of other sensory inputs in non-human mammals. Similar connections in the human are also likely to lag but the specific timings remain unknown. Preliminary studies have failed to demonstrate nerve fibres from nociceptive terminals in the fetal post-mortem spinal cord before 19 weeks.
    • p.5
  • The exact timing of the first nociceptive reflex responses to more traumatic mechanical stimulation is not known but they are unlikely to occur before the second trimester, somewhat later than responses to touch. It is known that the fetus withdraws from a needle from about 18 weeks and also launches a stress response following needle puncture. This stress response includes the release of hormones and neurotransmitters dependent on activity in areas of the midbrain. These findings confirm that signals about tissue damage are transmitted from the spinal cord and brainstem to the midbrain from at least 18 weeks.
    • p.5
  • The word ‘pain’ is used in different ways. The most frequent use, especially with respect to subjects that cannot communicate verbally, is in describing the behavioural response to noxious stimulation. However, if we accept this use, we are presented with the difficulty of distinguishing between the responses of simple versus complex organisms. Fruit fly larvae, for example, have been demonstrated to bend and roll away when approached with a naked flame but most people would agree that larvae do not feel pain in the way that we do.
    Ruling out the responses of larvae and similarly simple organisms as indicating pain is possible if we suggest that responses must include more than mere reflex responses to be labelled as a pain response. When someone reaches out and accidentally touches something very hot, there is an immediate tendency to drop the object. That reaction is entirely regulated by a simple loop of sensory neurons speaking to motor neurons in the spinal cord. Typically, the person will drop the object before there is any conscious appreciation of pain. The action of dropping the object indicates the presence of something noxious but does not necessarily indicate the presence of pain.
    • Box 1, p.6
  • Most pain researchers adopt a definition of pain that emphasises the sensory, cognitive and affective response to a noxious event. This understanding of pain is supported by the International Association of Pain (IASP) which defines pain as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage,or described in terms of such damage...pain is always subjective. Each individual learns the application of the word through experiences related to injury in early life’.1 By this definition, pain does not have primacy over subjectivity, existing before and in addition to subjectivity, but is experienced through subjectivity. It suggests that pain is a part of knowledge and requires the existence of a conceptual apparatus that can marshal all its dimensions into a coherent experience.
    Although there is considerable merit in the IASP definition of pain, it does tend towards a view of pain as being a constituent part of higher cognitive function. There is disquiet in denying a rawer, more primitive, form of pain or suffering that the fetus, neonate and many animals might experience.2–4 One possible solution is to recognise that the newborn infant might be said to feel pain, whereas only the older infant can experience that they are in pain and explicitly share their condition with others as an acknowledged fact of being.5
    Currently there is no immediately obvious way of resolving these arguments empirically. It is possible, however, to argue that even a raw sense of pain involves more than reflex activity and will, therefore, require the higher regions of the cortex to be connected and functional. The age when this minimum requirement is fulfilled is explored in the rest of this chapter.
    • Box 1, p.6
  • A connection from the skin to the spinal cord and brain is a basic requirement for the fetus to feel or be aware of pain. Again, it is important to emphasise that, while such input to the spinal cord and brain is necessary for perception of acute surgical pain, it is not sufficient. Activity in the spinal cord, brainstem and subcortical midbrain structures are sufficient to generate reflexive behaviours and hormonal responses but are not sufficient to support pain awareness.
    • p.7
  • Hormonal responses to needling show that there are functional brainstem and midbrain mediated reactions to noxious events but they, too, do not require higher brain processing to take place and can occur independently of sensory awareness. The specific relationship between pain and the release of hormones and neurotransmitters is unclear. In a prospective crossover study on 50 extremely low gestational age infants (less than 28 weeks of gestation), no difference in hormonal response was observed after heel lance15 and, in adult mice, it is difficult to distinguish changes in levels of naturally occurring opioids due to stressful handling from those due to tissue damage.
    • p.7
  • At 8 weeks, the fetal brain is profoundly immature and its surface layer, the cerebral cortex, is smooth, with no indication of the folds (sulci and gyri) that are so prominent later. There is also no internal cellular organisation in either the thalamus, which is the main source of sensory input to the cortex, or the cortex itself. The limbic system, an evolutionary older part of the brain, consisting of interconnected deep brain structures involved in various fundamental drives and regulatory functions, is already discernable and has began to form interconnections. The external surface of the brain is about 1 mm thick and consists of an inner and outer layer with no cortical plate, the structure that will gradually develop into the layers of the cortex proper.
    • pp.7-8
  • [T]he relocation of neurons from the subplate to the cortical plate also begins around 24 weeks, thus coinciding with the invasion of thalamic afferents. This relocation is extremely rapid from about 34 weeks, leading to the dissolution of the subplate as the extracellular matrix and other growth-related and guidance molecules disappear.21 The subplate has been observed to thin in the insula and in areas where cortical folding occurs rather earlier than the rest of the cortex, from at least 20 weeks. It is currently uncertain whether this thinning is due to earlier maturation and potentially earlier synaptic activity in these regions, some of which are key areas in the experience of pain in adults, 3 or attributable to incidental morphological changes.
    • p.8
  • While the study of anatomical connections between brain regions provides important information about developing pain processes, the existence of a connection is not evidence of its function. Connections viewed under the microscope between the thalamus and the cortical plate at 24 weeks, for example, may or may not transmit information from nociceptors upon tissue damage. Fetal magnetoencephalography has been used to effectively record fetal auditory and visual evoked responses and spontaneous brain activity of cortical origin from 28 weeks and fetal brain activation to sound has been demonstrated using functional magnetic resonance imaging (fMRI) from 33 weeks. It has not been possible to record directly from human fetal cortex to establish when cortical neurons first begin to respond to tissue damaging inputs. Near infrared spectroscopy with preterm infants in intensive care, however, has demonstrated localised somatosensory cortical responses in premature newborn infants (from 24 weeks) following noxious heel lance36 and venepuncture. More recently, EEG has demonstrated a clear, time-locked, nociceptive-evoked potential in preterm infants following heel lance. Thus, there is direct evidence of neural activity in primary sensory cortex following tissue damage in very premature infants equivalent to 24 weeks of gestational age.
    • p.9
  • Fetal behavioural responses have also been used as indicators of stress or pain. Shortly after the development of skin sensitivity, around 10 weeks, repeated stimulation results in hyperexcitability and a generalised movement of all limbs. After 26 weeks, this generalized movement gradually gives way to more coordinated behavioural responses that indicate improved organisation within the nervous system. Infants delivered at 26–31 weeks, for example, show coordinated facial expressions in response to heel prick, although these are immature compared to older infants. Four-D images of the fetus have also been reported to show fetuses ‘scratching’, ‘smiling’, ‘crying’ and ‘sucking’ at 26 weeks of gestational age.
    Although these later behavioural responses are not spinal cord reflexes, the responses are still unlikely to involve higher cortical centres. An anencephalic fetus withdraws from noxious stimulation, demonstrating that this response is mediated at a subcortical level. Similarly, infants with significant neonatal neurological injury due to a parenchymal brain injury respond to noxious stimulation with a pattern of behavioural reactions similar to infants without brain injury.
    • p.9
  • The cortex is required for both the discriminative and emotional aspects of the processing of noxious stimuli and both anatomical and functional studies show that cortical neurons begin to receive input about sensory events in the body and the external environment from 24 weeks. Long axonal tracts now course through the brain to the cortex and evoked responses in the primary sensory cortex indicate the presence of a spinothalamic connection and the ability of somatosensory cortical neurons to generate specific activity in response to tissue damaging stimulation. The primary sensory cortex is an important area in pain processing but it is only one of many areas that are active during pain experience. Other important areas include the secondary somatosensory, the anterior cingulate and the insular cortices. Although we may speculate that these regions will also be functionally active from 24 weeks, similar to primary sensory cortex, there is no evidence for this at the moment.
    It has been suggested that subcortical regions, including the brainstem, and transient brain structures, including the subplate, organise responses to noxious information at each stage of development and provide for a pain experience complete within itself at each stage. There is, however, no evidence or rationale for subcortical and transient brain regions supporting mature function. Although developing brain circuits often display spontaneous neuronal activity this activity is a fundamental developmental process and not evidence of mature function.
    • p.10
  • The fact that the cortex can receive and process sensory inputs from 24 weeks is only the beginning of the story and does not necessarily mean that the fetus is aware of pain or knows that it is in pain. It is only after birth, when the development, organisation and reorganisation of the cortex occurs in relation to the action and reaction of the neonate and infant to a world of meaning and symbols, that the cortex can be assumed to have mature features. The cortex is an important step beyond the spinal cord and brainstem because it facilitates pain experience by enabling the higher functions of cognition, emotion and self-awareness that are realized in the postnatal environment. Thus, there is good evidence for claiming that the cortex is necessary for pain experience but not sufficient.
    • p.10
  • It has been proposed that arguments around fetal pain can be resolved by the fact that the fetus never enters a state of wakefulness in utero.
    • p.10
  • Connections from the periphery to the cortex are not intact before 24 weeks of gestation. Most pain neuroscientists believe that the cortex is necessary for pain perception; cortical activation correlates strongly with pain experience and an absence of cortical activity generally indicates an absence of pain experience. The lack of cortical connections before 24 weeks, therefore, implies that pain is not possible until after 24 weeks. Even after 24 weeks, there is continuing development and elaboration of intracortical networks. Furthermore, there is good evidence that the fetus is sedated by the physical environment of the womb and usually does not awaken before birth.
    • p.11
  • Vaginal delivery may be considered a stress-inducing event to which most fetuses are subject. Fetuses born vaginally have higher levels of catecholamines, cortisol and endorphins than those born by elective caesarean section. It is unclear whether this stress response is related to the painful stimulus of head compression or to other factors, such as mild hypoxaemia or maternal stress. In normal labour, this evidence of fetal stress would be considered a normal fetal physiological response and the stress is thought to have benefits for fetal survival. The labour-related surge in steroids and catecholamines is an important factor in activating sodium channels and promoting the clearance of lung fluid. Babies born by caesarean section before the onset of labour have an increased incidence of respiratory complications, such as transient tachypnoea of the newborn. In addition, recent data show that elements of the stress response, perhaps noradrenaline or endorphins, have a short-term analgesic effect, so that babies born vaginally have an attenuated physiological and behavioural response to a painful stimulus compared with those born by elective caesarean section. Evidence of endogenous fetal analgesia during vaginal birth, as well as the role of catecholamines in promoting lung fluid reabsorption and the respiratory depressant actions of fetal opiate exposure, all suggest that the current approach to intrapartum analgesia, centred around maternal, rather than fetal, requirements for pain relief, is the correct one. The evidence that stress responses during normal vaginal delivery have benefits cannot, however, be readily extrapolated to stress responses during pregnancy.
    • p.14
  • The fetal response to noxious stimuli, described in detail in section 2, comprises two elements, both of which need to be present for the fetus to feel pain. The first of these involves nociception and a physiological stress response to it, while the second requires cortical processing of the nociceptive stimulus to produce a negative emotional perception. The evidence clearly suggests that the autonomic and endocrine pathways are in place for the fetus to mount a stress response as early as 18 weeks of gestation, with increases in cerebral blood flow, catecholamines and cortisol observed following invasive procedures. These responses can be attenuated by administration of fetal analgesia at the start of the procedure. It is worth noting that the fetal stress response can be elicited by a number of non-painful stimuli; the most extensively described is the response to acute hypoxia, where many of the components, such as increased cerebral blood flow, are part of a coordinated fetal response to minimise damage to organs such as the brain and heart. Increased cerebral blood flow, catecholamines and cortisol cannot therefore be interpreted as evidence that the fetus is feeling pain.
    • pp.14-15
  • Data gathered from premature babies on intensive care units suggest that exposure to repeated, strong stimuli can alter cardiovascular responses to a painful stimulus later in infancy and that fetuses born with higher cortisol levels in cord blood, owing to vaginal delivery, have an altered stress response to vaccination. These data suggest that fetal exposure to ‘stress’ in utero can modulate the later function of the hypothalamic pituitary axis. From this, it has been suggested that reducing the magnitude of the initial stress response, for example by using fetal analgesia, will have a beneficial effect. However, the degree to which these effects can be observed following fetal exposure to a painful stimulus remains uncertain, as the majority of studies to date are postnatal and refer to intense, repetitive stimuli that are not normally experienced in utero. The uncertain benefit of attenuating the fetal stress response to a noxious stimulus in utero by administering analgesia needs to be balanced against the practical difficulties to the administration of effective fetal analgesia, as well as the possibility of adverseeffects.
    • p.15
  • In contrast to the endocrine and haemodynamic responses to a noxious stimulus, which are easily quantified, it has not been possible to directly measure the cortical response to such a stimulus. Assessments about the gestation at which a fetus could feel pain are therefore made on the basis of the existence of the necessary neural pathways for pain perception, particularly the nature of thalamocortical connections (see section 2), as well as indirect evidence for functionality based on evoked responses and evidence for a sleep–wake cycle of EEG activity. Interpretation of existing data indicates that cortical processing of pain perception, and therefore the ability of the fetus to feel pain, cannot occur before 24 weeks of gestation and that the nature of cortical activity becomes more complex as gestation advances from this point. It is reasonable to infer from this that the fetus does not require analgesia for interventions occurring before 24 weeks of gestation. Furthermore, and importantly, the evidence that analgesia confers any benefit on the fetus at any gestation is lacking.
    • p.15
  • [A]s current evidence indicates the inability of the fetus to experience pain, certainly before the end of the second trimester, it should not be necessary to consider the need for fetal analgesia.
    • pp.17-18
  • The implications for clinical practice of the neurobiological evidence presented in section 2 have been considered. Interpretation of existing data suggests that cortical processing and therefore fetal perception of pain cannot occur before 24 weeks of gestation. It is reasonable to infer from this that the fetus does not require analgesia for interventions occurring before 24 weeks of gestation. Diagnostic or therapeutic procedures that involve the fetus directly are very uncommon but do occur and can be associated with a stress response. However, this does not indicate that the fetus is aware or can feel pain. The case for administering analgesia before an invasive procedure (in addition to maternal general anaesthesia) after 24 weeks when the neuroanatomical connections are in place, needs to be considered together with the practicalities and risks of administration of fetal analgesia in continuing pregnancies and the uncertainties over long-term effects. Evidence that analgesia confers any benefit on the fetus at any gestation is lacking but should be a focus of future research that will need to include medium and longer-term as well as immediate outcomes.
    • p.19
  • Will the fetus/baby feel pain?
    No, the fetus does not experience pain. Pain relates to an unpleasant sensory or emotional response to tissue damage. To be aware of something or have pain, the body has to have developed special sensory structures and a joined-up nerve system between the brain and the rest of the body to communicate such a feeling. Although the framework for the nervous system in the growing fetus occurs early, it actually develops very slowly. Current research shows that the sensory structures are not developed or specialised enough to experience pain in a fetus less than 24 weeks.
    After 24 weeks, it is difficult to say that the fetus experiences pain because this, like all other experiences, develops postnatally along with memory and other learned behaviours. In addition, increasing evidence suggests that the fetus never enters a state of wakefulness inside the womb. The placenta produces chemicals that suppress nervous system activity and awareness.
    • 4. Information for women and parents, p.20
  • Will the process hurt the baby?
    No. To be hurt, you need to feel pain. Current research shows that the sensory structures are not developed or specialised enough for a fetus to experience pain less than 24 weeks. Pain experience after 24 weeks depends upon a psychological development that is restricted before birth. See the question ‘Will the fetus/baby feel pain?’
    • 4. Information for women and parents, p.20
  • Does an anaesthetic or the pain relief I receive affect the baby?
    If you are given a general anaesthetic for a diagnostic procedure, the substances used in this will cross the placenta to the baby. The effect will happen more slowly to the baby and will not cause any harm to the baby.
    If you are given other forms of pain relief, there is evidence that they will cross the placenta to the baby, but the doses are not large enough to cause any harm.
    • p.22
  • Can the baby be given pain relief?
    No. Current research shows that the sensory structures are not developed enough or specialized enough to respond to pain in a fetus of less than 24 weeks. See question on ‘Will the fetus/baby feel pain?’ In later pregnancy, when the fetus/baby is over 24 weeks, we do not yet have enough knowledge to know if providing pain relief would be beneficial. This means that it is extremely difficult to know what kind of pain relief should be used, how any pain relief should be given and whether it would be safe and effective. If pain relief was to reach the baby inside the womb, this would mean giving the mother larger and potentially dangerous doses to try and make sure enough crossed the placenta to the baby. This may cause more harm than benefit. Injecting pain relief drugs directly into the baby would increase the risk of miscarriage.
    • p.22
  • Will the baby suffer/feel pain?
    No, the fetus does not experience pain. In addition, increasing evidence suggests that the fetus never enters a state of wakefulness inside the womb and that the placenta produces chemicals that suppress nervous system activity and awareness. Feticide is always offered when an abortion is carried out after 21 weeks and 6 days, unless the fetal abnormality is lethal and will cause death of the fetus during or immediately after delivery. A doctor who is specially trained in fetal medicine carries out feticide. To ensure the baby is not born alive, the doctor will inject a solution of potassium chloride directly into the fetal heart. Before anything else is done, the fetal heart will be checked to ensure it has stopped. Death is extremely quick after feticide.
    • p.22
  • Will the baby be in pain in the womb because of the condition that has been diagnosed?
    This is very unlikely. Current research shows that the sensory structures are not developed or specialised enough to respond to pain in a fetus of less than 24 weeks. Even after 24 weeks it is difficult to say that the fetus experiences pain, because this, like all other experiences, develops postnatally along with memory and other learned behaviours. Moreover, the environment of the womb is usually protective with the fetus floating in the warm amniotic fluid.
    • p.22
  • The experience of pain needs cognitive, sensory and affective components, as well as the necessary anatomical and physiological neural connections.
    Nociceptors first appear at 10 weeks of gestation in the fetus but they are not sufficient for the experience of pain in themselves. That requires that electrical activity is conducted from the receptors into the spinal cord and to the brain. Fibres to nociceptor terminals in the spinal cord have not been demonstrated before 19 weeks of gestation, although it is known that the fetus withdraws from a needle and may exhibit a stress response from about 18 weeks. At this stage, it is apparent that activity in the spinal cord, brain stem and mid-brain structures are sufficient to generate reflex and humoral responses but not sufficient to support pain awareness. At the same time, completion of the major neural pathways from the periphery to the cortex, at around 24 weeks of gestation, heralds the beginning of a further neuronal maturation. The proliferation of cortical neurons and synaptic contacts begins prenatally but continues postnatally. Magnetic imaging techniques have recorded fetal auditory and visual responses from 28 weeks but it has not been possible to record directly when cortical neurons first begin to respond to tissue damaging inputs, although there is evidence of neural activity in primary sensory cortex in premature infants (around 24 weeks). It has been suggested that subcortical regions can organise responses to noxious stimuli and provide for the pain experience complete within itself but there is no evidence (or rationale) that the subcortical and transient brain regions support mature function.
    Thus, although the cortex can process sensory input from 24 weeks, it does not mean that the fetus is aware of pain. There is sound evidence for claiming the cortex is necessary for pain experience but this is not to say that it is sufficient.
    • 5. Conclusions, p.23
  • [N]one of us has any memory of the pain of being born, which is not to say that birth, from the fetus’ point of view, could not still have been a painful process.
    • 5. Conclusions, p.23-24
  • [I]n the previous report, it was recommended that the use of analgesia be considered where the fetus was over 24 weeks of gestational age. However, this more recent review has concluded that the evidence that the fetus can and does experience pain is less compelling and accordingly the benefit of administering analgesia is less evident, while the risks and practicalities of so doing remain. So on the basis of ‘first do no harm’, prior to the procedures described in this report, analgesia is no longer considered necessary, from the perspective of fetal pain or awareness.
    • p.24

See also

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Painful Quotes about life

 
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