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Commentary: The COVID-19 Pandemic Demonstrates the Urgency of Including Pregnant Individuals in Clinical Research

Key findings

  • Medical societies were unsuccessful in advocating for inclusion of pregnant individuals in the COVID-19 vaccine trials that formed the basis of FDA emergency use authorizations and CDC guidance
  • Tendencies that contribute to exclusion of pregnant individuals from trials include narrow focus on fetal risk rather than the health of the dyad, overlooking potential benefit and erroneously labeling pregnant populations as ''vulnerable''
  • Exclusion of pregnant individuals from trials of COVID-19 vaccines has led to inconsistent policies, for example about priority for vaccination and whether pregnant individuals may be vaccinated at pharmacies
  • Another result of the evidence gap is that public health agency and professional society guidelines are tepid in endorsing COVID-19 vaccination for pregnant individuals
  • Reasons for optimism are that almost all mainstream media outlets have featured articles about evidence gaps in pregnancy in the context of COVID-19 vaccines, so there is increasing public support for including pregnant individuals in research

One of the many inequities in health care is that pregnant individuals are routinely excluded from clinical trials of drugs and vaccines. This has had negative repercussions not just for individuals, but also for public health, including during the COVID-19 pandemic.

For example, the exclusion of pregnant individuals from trials of COVID-19 vaccines has led to inconsistent policies. When the vaccines first became available in the U.S., some states did not mention pregnancy as a condition for priority eligibility. Some pharmacies and other locations are denying vaccination to eligible pregnant individuals despite professional recommendations and even endorsement from physicians.

History demonstrates that contradictory public health messaging, in combination with lack of evidence about vaccine safety in pregnancy, can lead to delay or denial of access to life-saving interventions, delays in epidemic control and potentially terminations of otherwise desired pregnancies.

In a commentary published in MedIlona Goldfarb, MD, MPH, maternal-fetal medicine specialist in the Department of Obstetrics and Gynecology at Massachusetts General Hospital, and colleagues in the Center for Bioethics at the University of North Carolina at Chapel Hill, examine several myopic viewpoints that must be confronted in order to move toward ethical inclusion of pregnant individuals in COVID-19 clinical research. They also review the latest guidance on COVID-19 vaccination during pregnancy and conclusions to date from the Centers for Disease Control and Prevention (CDC) surveillance.

Protective Tendencies

Several protective tendencies contribute to exclusion of pregnant individuals from clinical trials:

  • The tendency to focus narrowly on fetal risk, rather than considering the health of the dyad, even though maternal disease and death also present fetal risk and longer-term risk for the child
  • The tendency to focus on intervention-specific risks without acknowledging harms of inaction to the pregnant individual, fetus or both
  • The tendency to overlook potential benefit, which might actually be greater for pregnant than non-pregnant individuals, either because some conditions present greater risk in pregnancy or because the intervention may benefit two entities
  • The tendency to emphasize immediate research-specific risks over risks that will accrue clinically if the research is not done. Containing intervention risk within the controlled setting of a trial minimizes health risks for pregnant participants and their offspring, which otherwise would manifest in clinical settings where oversight of safety outcomes is not formalized and the potential for harm is more widespread
  • The tendency to label pregnant populations as ''vulnerable,'' a legal category intended to denote people without the capacity to provide free and informed consent. Pregnant individuals are more medically complex than other adults, but are as intellectually and morally competent to make their own decisions for themselves and their offspring. Furthermore, according to a study by Dr. Goldfarb and colleagues, evidence suggests pregnant individuals want to participate in clinical research, often for similar reasons as non-pregnant people

CDC Surveillance Data

Protective tendencies can be well-intentioned, but if they unfairly constrain how pregnant individuals can interact with and benefit from clinical research, they must be challenged. Unfortunately, the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal–Fetal Medicine (SMFM) were unsuccessful in advocating for the inclusion of pregnant individuals in the COVID-19 vaccine trials that formed the basis of FDA emergency use authorizations and CDC guidance.

Subsequently, it's been well established that pregnant individuals are at increased risk of severe disease and death compared with other adults who develop COVID-19. A trial of one authorized vaccine in pregnant individuals is finally underway, but the best available safety dataset is from the CDC, which had recorded 128,306 COVID-19 vaccinations during pregnancy as of June 28, 2021. However, only 5,103 of those individuals were enrolled in the associated pregnancy registry.

Preliminary CDC analyses have not identified any safety concerns for pregnant individuals who were vaccinated or for their fetuses/neonates. Additional follow-up is needed, though, particularly for those vaccinated in the first or second trimesters of pregnancy.

The Latest Guidance

The World Health Organization (WHO) has reversed its earlier stance that the Pfizer/BNT, Moderna and Johnson & Johnson COVID-19 vaccines should be administered to pregnant individuals only if they are part of other high-risk groups, such as health care workers and people whose comorbidities increase their risk of COVID-19. The WHO now recommends the use of all three vaccines "when the benefits of vaccination to the pregnant woman outweigh the potential risks."

The CDC holds that pregnant individuals "are eligible" for COVID-19 vaccines; ACOG and SMFM say they should "have access." These cautious statements are a consequence of the evidence gaps that resulted from excluding pregnant individuals from trials. Guidelines for other high-risk populations offer a stronger endorsement of COVID-19 vaccination.

Reasons for Optimism

Almost all mainstream media outlets have featured articles about evidence gaps in pregnancy in the context of COVID-19 vaccines. Never has there been so much public support for including pregnant individuals in research, as there is increasing recognition that responsible research in pregnancy is possible. It is imperative to build on this public discourse toward responsible, proactive inclusion of pregnant individuals in biomedical research.

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