Zebra Fact Check developed this resource to supplement a critique of an May 13, 2022 fact check from Logically Fact Check.
See the search parameters and results (yours may vary from ours despite the search terms matching) here.
Evidence in neonates of stress responses to surgical insults and their prevention with analgesia has led to increased awareness of pain and the need for analgesia in newborns. This raises the obvious question if and when the fetus can feel pain. The critical thalamo-cortical connections for nociception form from 20±26 weeks, while substantial hormonal and circulatory stress responses to invasive procedures are observed by 20 weeks.
Indeed, the Royal College of Obstetrics and Gynaecology has recommended that analgesia should be considered if performing potentially painful interventions on the fetus after 24 weeks gestation .
Conclusions Evidence regarding the capacity for fetal pain is limited but indicates that fetal perception of pain is unlikely before the third trimester.
Exposure of the fetus and premature newborn to pain has been associated with long-term alterations in pain response thresholds, as well as changes in behavioral responses related to the painful stimuli. Anesthesia has been shown to reduce the stress response to painful stimuli in the fetus and newborn infant. It is important to consider the long-term effects of the noxious stimuli on neurophysiological development when painful procedures are planned.
2008: Fetal awareness
Evidence is imprecise, but the fetus is probably not capable of being aware before 16 weeks, and has the mechanisms necessary for awareness after 26 weeks. Administering fetal analgesia is not straightforward, and theoretical benefits for the fetus must be weighed against actual risks for the mother. […]
Whether fetuses have the sensation of pain or not, and whether they should be anesthetized before feticide, are issues under debate. We were aware that there is evidence to show that fetal pain and awareness are very likely to exist after 26 weeks of gestation when thalamo-cortical neuron connections are established  and intrathoracic or intracardiac puncture may be painful.
We know from our everyday experience that there is no substantial difference between the behaviours and responses of babies at 23, 24 and 25 weeks. Over the last 20 or more years, researchers have accumulated good observational, experimental and pathophysiological reasons to consider that babies at these gestations do feel pain, that they benefit from analgesia, and that pain experiences in early life cast neurophysiological and behavioural shadows far down childhood.
Our data show that there is consistent evidence of the possibility for the fetus to experience pain in the third trimester, and this evidence is weaker before this date and null in the first half of pregnancy.
The neuroscientific evidence presented in the recent studies does not outrightly reject the possibility of fetal pain, even though there are a wide range of opinions and controversies at all the stages of its neurobiology. Whether the fetal capacity of pain develops at around 18 weeks of gestation or later after 23 weeks of gestation is still a matter of debate.
This is the first description of a recordable acute pain model in the human fetus by the use of a facial expression–based tool. The possibility to assess pain-related intrauterine behaviours would allow not only for the monitoring of the efficacy of anaesthetic procedures in the fetus but would also open the way to explore the evolution of pain-related facial responses during the fetal neurodevelopment. This method may pave the way for objective assessments of pain in fetuses, should it endure the steps of formal validation studies.
Denial of fetal pain persists “in large part because fetal pain is often cited as a reason to restrict access to termination of pregnancy or abortion” (Derbyshire and Bockmann 2020). But the data that confirm the existence of fetal pain is extensive and compelling. [formatting adjusted by ZFC]