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A fetal pain 'denier' rethinks the science

Photo: Lennart Nilsson’s 1965 cover photo for LIFE magazine: “Living 18-week-old fetus shown inside its amniotic sac.” It was the best-selling issue of all time.

By TATIANA PROPHET

“Gestational Age Bans: Harmful at Any Stage of Pregnancy” is the title of a 2020 article by Megan K. Donovan of the Alan Guttmacher Institute, the publishing arm of Planned Parenthood.

“Gestational age bans have long been a favored tactic of antiabortion activists and politicians as they seek to undermine and ultimately overturn the constitutional right to abortion,” she wrote. “In the past, such efforts were usually cloaked in supposed justifications that obscured the end goal. For example, bans on abortion at or around 22 weeks after the last menstrual period (LMP) have been propped up with unscientific claims about that stage of pregnancy, such as that a fetus can feel pain or that ending the pregnancy will result in mental health complications.”

Donovan’s source on pain is London’s Royal College of Obstetricians and Gynaecologists, which in 2010 published a “Working Party Report” titled “Fetal Awareness.”

The report’s authors concluded that before 24 weeks’ gestation, a noxious or tissue-damaging stimulation does not cause pain because the cerebral cortex is not yet connected to “the periphery” and that further development and cognition is necessary for a fetus to actually feel pain.

The report acknowledges that “nociceptors” develop at 10 weeks’ gestation, meaning that the nervous system can respond to noxious stimulus at that point; and post 18 weeks, a fetus may exhibit a “stress response” to a needle, indicating that the “mid-brain” is receiving signals.

In summary, the Royal College concludes: “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.”

The article by Donovan links to a legislative explainer on 20-week bans that states that there is “scientific consensus” on fetal pain; yet the study she links to, from 2005, acknowledges in the abstract that evidence on fetal pain is “limited.”

“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.” They add that sedation during prenatal surgery is designed to prevent the fetus from wiggling and not to prevent pain.

On January 14, 2020, something unique happened: two scientists on opposite sides of the abortion issue came together to write a paper titled: “Reconsidering Fetal Pain,” in the Journal of Medical Ethics.

Stuart Derbyshire and John C. Bockmann argue that neuroscience cannot definitively rule out pain before 24 weeks.

“Most reports on the possibility of fetal pain have focused on developmental neuroscience. Reports often suggest that the cortex and intact thalamocortical tracts are necessary for pain experience. Given that the cortex only becomes functional and the tracts only develop after 24 weeks, many reports rule out fetal pain until the final trimester. Here, more recent evidence calling into question the necessity of the cortex for pain and demonstrating functional thalamic connectivity into the subplate is used to argue that the neuroscience cannot definitively rule out fetal pain before 24 weeks. We consider the possibility that the mere experience of pain, without the capacity for self reflection, is morally significant. We believe that fetal pain does not have to be equivalent to a mature adult human experience to matter morally, and so fetal pain might be considered as part of a humane approach to abortion.”

The paper is even more stunning because Derbyshire had previously written a paper denying pain felt by the fetus: “Does the Fetus Feel Pain?” in which he concluded that “the basic physical mechanisms we need to feel pain develop in a fetus from about the 26th week of pregnancy.”

This year, however, two studies about cortical-compromised individuals led Derbyshire, a professor of cognitive science, to change his tune.

“Regardless of whether there ever was a consensus, however, it is now clear that the consensus is no longer tenable,” he wrote. “Several papers have now been published suggesting that the necessity of the cortex for pain experience may have been overstated. One study has, for example, demonstrated continued pain experience in a patient with extensive damage to cortical regions generally believed to be necessary for pain experience. A further study has demonstrated activation of areas generally thought to generate pain in subjects congenitally insensitive to pain but receiving noxious stimuli. While certainly not definitive, those two studies appear to neatly dissociate pain experience from the cortex.

“In addition, previous proponents of fetal pain speculated that neural activity in the subplate might support fetal pain experience. At 12 weeks’ gestation there are the first projections from the thalamus into the cortical subplate. The subplate is a transient developmental structure that forms underneath the cortical plate proper. Neurons destined for the cortical plate first migrate into the subplate where they wait until the cortical plate above is sufficiently mature and then the neurons migrate to their mature position in the cortex. The subplate then gradually withers away and becomes white matter. Recent work with ferrets has demonstrated that auditory stimuli trigger neural activity in the subplate that is topographically highly similar to the activity observed in the more mature auditory cortex.”

Technical language aside, other studies that predate “Reconsidering Fetal Pain” take several approaches that vary from the Royal College’s uni-pronged approach. One study argued that endocrine hormones denoting a stress response are present as early as 18 weeks.