Understanding willingness and barriers to participate in clinical trials during pregnancy and lactation: findings from a US study.

Background: Due to the exclusion of pregnant and lactating people from most clinical trials, there is an incomplete understanding of the risks and benefits of medication use in these populations and therapeutic decision-making is often conducted without adequate evidence. To change this paradigm, it is imperative to understand the perspectives of pregnant and lactating individuals concerning their participation in clinical trials.

Objectives: To describe attitudes, perceptions, barriers, and preferences of pregnant and postpartum people in the United States (US) regarding participation in clinical trials and to identify factors influencing participation.

Methods: In November 2022, individuals aged ≥ 18 residing in the US who self-identified as pregnant or pregnant within the last 12 months were invited to complete an online survey about their perspectives regarding clinical trial participation. The survey included questions about demographic characteristics, health history, behaviors, and willingness to participate in clinical trials while pregnant and/or lactating. Multivariable logistic regression models were fit to identify predictors of clinical trial participation.

Results: Among the 654 respondents, 34.8% and 40.9% reported being likely or extremely likely to participate in a clinical trial for a new medication while pregnant or lactating, respectively; and 24.5% and 41.7% for a new vaccine while pregnant or lactating, respectively. Higher educational attainment (≥ Bachelor's degree) was associated with greater likelihood of clinical trial participation in pregnancy (odds ratio (OR) = 1.50, 95% Confidence Interval (CI): 1.01, 2.25 for medications; OR = 2.00, 95% CI: 1.28, 3.12 for vaccines). Chronic medical conditions were associated with a greater likelihood of participation in clinical trials for vaccines during lactation (OR = 1.59, 95% CI: 1.07, 2.36). The most cited motivator for participation in a clinical trial while pregnant or lactating was anticipated personal medical benefit (85.8% and 75.6%, respectively), while the primary deterrent was possible risk to the fetus or baby (97.9% and 97.2%, respectively).

Conclusions: Willingness of a US sample to participate in clinical trials while pregnant or lactating varied by demographics and health status, with safety to the fetus being a nearly universal concern. These findings have implications for enhancing inclusion of pregnant and lactating people in clinical research and developing effective and equitable recruitment strategies.