AbstractThere is a consistent view in the literature that research on pregnant woman with psychoses is ethically questionable or impermissible. This paper provides a critical appraisal of these views by asking whether pharmacologic research on pregnant women with psychosis for maternal, fetal, and newborn benefit is ethically permissible. We examine separately the documented clinical benefits and risks to the pregnant patient, the fetal patient, and the neonatal and pediatric patient. The outcomes reported in the pertinent literature do not support the conclusion that pharmacologic management of psychosis during pregnancy results in documented, unacceptable risk to the pregnant, fetal, or neonatal patient and is therefore ethically ruled out. Claims that research on the pharmacologic management of psychosis during pregnancy is ethically impermissible because of unacceptable risk of harm to pregnant, fetal, neonatal, or pediatric patients cannot therefore be supported. Having shown that such research is permissible, we then ask what ethical considerations should guide study design. We show that Phase I studies are appropriate and can meet the requirements of the Common Rule, which are more specific than international guidance. As a matter of professionally responsible obstetric practice, pregnant women with psychoses should be included, and not be neglected, in research for both maternal and fetal benefit.