Scientific, ethical, and legal considerations for the inclusion of pregnant people in clinical trials

Clinical trials to address the COVID-19 public health emergency have broadly excluded pregnant people from participation, illustrating a long-standing trend of clinical trial exclusion that has led to a clear knowledge gap and unmet need in the treatment and prevention of medical conditions experienced during pregnancy and of pregnancy-related conditions. Drugs (includes products such as drugs, biologics, biosimilars and vaccines) approved for a certain medical condition in adults are also approved for use in pregnant adults with the same medical condition, unless contraindicated for use in pregnancy. However, there are limited pregnancy-specific data on risks and benefits of drugs in pregnant people, despite their approval for all adults. The United States Food and Drug Administration–approved medical products are used widely by pregnant people, 90% of whom take at least 1 medication during the course of their pregnancy despite there being sparse data from clinical trials on these products in pregnancy. This overall lack of clinical data precludes informed decision-making, causing clinicians and pregnant patients to have to decide whether to pursue treatment without an adequate understanding of potential effects. Although some United States Food and Drug Administration initiatives and other federal efforts have helped to promote the inclusion of pregnant people in clinical research, broader collaboration and reforms are needed to address challenges related to the design and conduct of trials that enroll pregnant people, and to forge a culture of widespread inclusion of pregnant people in clinical research. This article summarizes the scientific, ethical, and legal considerations governing research conducted during pregnancy, as discussed during a recent subject matter expert convening held by the Duke-Margolis Center for Health Policy and the United States Food and Drug Administration on this topic. This article also recommends strategies for overcoming impediments to inclusion and trial conduct.