The Facts on Fetal Pain

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Today’s guest blog was submitted anonymously.

Pregnant women, medical professionals, and the general public care about fetal pain and deserve the facts(1,2,3,4). Fetal pain perception is likely by 15-20 weeks gestation(5,6) and possible by 12 weeks(7,8,9).

Pro-choice medical associations, however, state that the fetus undergoing an induced abortion is unconscious and cannot feel pain until after 24 weeks, 28 weeks, or even later due to an immature cortex(10,11,12). This contradicts current medical practice in fetal surgery and neonatal medicine(13,14,15). Specifically, the American Society of Anesthesiologists, the North American Fetal Therapy Network, and numerous fetal surgery experts recommend fetal anesthesia in all invasive fetal procedures(14,16,17). Neonatologists care for babies born at 22-23 weeks, with increasing cases at 21 weeks(18,19,20,21). It is the medical standard of care to directly treat pain in these infants, even while pro-choice medical organizations maintain that these infants cannot feel pain until weeks to months later. A fetus treated for pain during fetal surgery at 15-16 weeks (22,23,24) and the premature infant in the NICU at 22 weeks have the capacity to feel pain during an abortion. 

The scientific evidence for fetal pain rests on the following: 

1. The fetus responds to skin-breaking procedures with dramatic changes in behavior, stress hormones, and metabolism from the earliest ages studied(9,14,25,26).

These stress responses include facial expressions of pain by 23 weeks(17,27,28,video), vigorous body and breathing movements by 15-18 weeks(29,30,31), and sharp increases in ‘fight or flight’ stress hormones by 18 weeks(29,30). These same pain responses are seen in infants, older children, and adults and are alleviated when anesthesia is given. Peer-reviewed research has consistently shown that fetal anesthesia is necessary and effective(14,16,23,32). Fetal surgeons have now developed the first fetal pain assessment tool to improve pain management for the fetus during and after invasive procedures(17). 

2. Anatomic and behavioral evidence suggests the fetus is capable of pain awareness.

Multiple areas of the brain are involved in consciousness and pain perception(33). Many of these areas develop in the first trimester (<14 weeks). By 12-15 weeks, pain transmission pathways have developed that are capable of sending pain signals from the skin to multiple areas of the brain, including the brainstem, thalamus, and cortical subplate(1,7,34,35). By 14 weeks, the fetus demonstrates purposeful behavior, social awareness, and a basic level of consciousness(36,37). By 16 weeks, the fetus hears and responds to music with movements of the mouth and tongue(38). Connections between the thalamus and cortex develop after 23-24 weeks gestation(39,40), yet even prior to this, premature infants are treated for pain in the NICU, and fetuses acutely react to pain during fetal surgery. 

3. The brain does not need to be fully developed to experience pain.

Scientific research has demonstrated that pain perception and consciousness exist even when the cortex is absent, damaged, or immature(33,41,42,43). The brain has redundant pain pathways(33,44) and the fetal brain has pathways to the cortical subplate that do not exist in older children or adults(45,46). The International Association for the Study of Pain (IASP) defines pain as an unpleasant sensory and emotional experience caused by tissue damage(47). However, fetuses and newborns likely experience pain differently than adults(7), with both short and long-term consequences(48). The updated 2020 IASP definition states that pain does not have to be verbalized to matter emotionally and ethically(47). Additionally, fetuses and preterm infants likely experience more pain than adults(49), not less, due to underdeveloped pain inhibition mechanisms and lower pain thresholds(6). The neonatal standard of care is to avoid, ameliorate or treat edge of viability premature infants’ pain(7,14,15). Untreated pain damages the brain, particularly early pain experiences, resulting in increased pain sensitivity, altered neurodevelopment, and long-term effects(15).

Conclusion 

Prevention and treatment of fetal pain is medically and ethically necessary. Every major medical organization recognizes that prevention and treatment of pain is a human right(50,51,52), yet not all extend this right to the human fetus prior to birth. Facts about fetal pain are important to pregnant women and to the public. These facts are necessary for true informed consent. Fetal pain perception is likely by 15-20 weeks gestation(5,6) and possible by 12 weeks(7). Pro-choice medical associations have overlooked substantial newer research by maintaining that the immature cortex makes fetal and neonatal pain impossible before 24-28 weeks or later(12,53). Based on this outdated hypothesis, pain was underrecognized and undertreated for decades during surgical procedures, not only in the fetus(25,29,30), but also in the infant(54,55,56).

Today, we know better. Extensive scientific and clinical data support the recognition and treatment of pain in the fetus. As with surgeries for infants, older children, and adults, anesthesia is directly and routinely administered during fetal surgery to guarantee the least possible pain(14). A fetus that can perceive pain during fetal surgery has the capacity to feel pain during an induced abortion. Consistent recognition of fetal pain capacity offers the clearest picture of these facts.

Citations

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