By Stuart WG Derbyshire
For more than thirty years I have written about fetal pain. And for almost as long I have been asked the same question: “But can you be sure?”
For a long time I was sure. Neuroscience had seemingly established the cortex as necessary for conscious experience, and the cortex does not become a functional unit until well into the final trimester of pregnancy. In addition, pain was understood as a self-reflexive conscious experience that was hard to reconcile with the immature brain and mind of the fetus or newborn.
That did not mean there was no place for analgesia when performing clinical procedures with the fetus or newborn. In the 1980s, clinical trials showed that babies undergoing surgery had dramatically better outcomes when given adequate analgesia. Mortality fell, complications decreased, and physiological stability improved. On that basis, the routine use of analgesia in neonatal surgery became morally required, and some argued that the improved outcomes proved the neonate could feel pain.
Those trials did not prove that neonates consciously experienced pain. What they demonstrated was that surgery without adequate anaesthesia produced a harmful physiological stress response. Preventing that response improved survival. That improvement showed that untreated injury is physiologically damaging, but it did not establish the presence of a subjective pain experience.
Nevertheless, in the neonatal context the outcome evidence was so strong that philosophical arguments about experience could reasonably be set aside. When treatment clearly improves survival and reduces harm, that is sufficient justification for analgesia.
Fetal medicine is different. Fetal surgery is rare, trials are limited, and analgesia has not been tested as an independent determinant of fetal outcome. Arguments that the fetus feels pain therefore rested more heavily on neural development, which was the evidence I rejected until recently. But over the past two decades evidence has accumulated suggesting that the cortex might not be necessary for pain experience, and that subcortical structures might support a less reflective, more immediate sensation of pain.
By around 18 weeks’ gestation, fetal development is sufficiently complex to meet the requirements of such an experience, and claims about possible pain can no longer be so easily dismissed. Yet there is still no means to conclusively demonstrate that pain is present, or to definitively rule it out.
Some philosophers argue that uncertainty about pain should trigger a precautionary response: if we cannot rule out pain, we should treat the entity as if it is pain-capable. This approach has intuitive appeal and has influenced debates about fetal, animal, and artificial sentience. But precaution only works when the harms of action and inaction are clearly asymmetrical. In fetal and neonatal medicine that asymmetry is often absent.
Analgesic interventions carry their own risks, including physiological instability, pharmacological exposure, and procedural delay. In neonatal intensive care, clinicians sometimes worry that rapid intervention produces better outcomes than a carefully staged “pain-free” procedure. In fetal surgery, additional steps may increase risk to the pregnant woman. In abortion, no fetal outcome benefit can ever be demonstrated.
When both intervention and non-intervention involve uncertain harms, it is not obvious which course is truly the more cautious. To assume that providing analgesia is automatically the safer moral choice is itself a judgement rather than a scientific conclusion.
Compassion plays a powerful and necessary role in medicine. Few clinicians are comfortable with even the possibility of causing suffering. But compassion is not exhausted by avoiding potential pain. It must also consider long-term outcomes, proportionality of risk, and the interests of those whose bodies and futures are directly involved.
The deeper difficulty is that the uncertainty itself may never disappear. Pain is a subjective experience, but fetuses and very young infants cannot tell us what they feel. We must infer experience from physiological responses, movements, and patterns of brain activity. Those indicators are informative, but they cannot eliminate the gap between bodily reaction and conscious experience.
That means decisions about fetal and neonatal pain can never be purely scientific. They inevitably involve ethical judgement. Where strong outcome evidence exists, as in neonatal surgery, the decision is relatively straightforward. Treatment improves survival and reduces harm, and that is enough to justify intervention.
But in many other contexts the evidence is sparse or impossible to obtain. In those situations, we are not discovering the right answer through science alone. We are deciding how to act in the face of uncertainty.
Medicine routinely operates under conditions of incomplete knowledge. Fetal and neonatal pain are not exceptions. The important question is not whether we can eliminate uncertainty, but how honestly we acknowledge it.
In the end, the fetus or neonate will never be able to tell us whether we were right or wrong. That means the responsibility for these decisions, and for their moral justification, rests entirely with us.
Paper title: Assessing fetal and neonatal pain: ethical implications of epistemic uncertainty
Author: Stuart WG Derbyshire
Affiliations: Department of Psychology, National University of Singapore
Competing interests: None to declare
Social media accounts of post author: @painfulgains