Evaluating representation of racially and ethnically minoritized populations in perinatal research: a single-site comparison of study enrollment and hospital population

Perinatal research faces persistent challenges to inclusive recruitment due to time-limited eligibility, caregiving demands, and postpartum recovery, with additional barriers disproportionately affecting racially and ethnically minoritized populations. Despite recognition of these challenges, limited real-world evidence exists on whether commonly used recruitment approaches yield study populations that reflect the diversity of the clinical populations they serve. To address this gap, we examined the demographic diversity of participants enrolled in three perinatal studies using differing recruitment strategies and compared each study population to the overall birthing population of a single women’s specialty hospital. We compared the hospital’s birthing population to the participant demographics of three observational studies conducted concurrently (2021–2023) with differing recruitment strategies. Study A, which consisted of a 30-minute online survey, used indirect outreach without compensation; study B, which consisted of a 30-minute online survey, used direct, remote outreach with $15 compensation; and study C, which involved a blood draw and a 30-minute visit, combined indirect and in-person clinic-based recruitment, offered Spanish-language support, and provided $50 compensation. One-sample tests of proportions were used to compare the demographics (race, ethnicity, age) of each study to that of the hospital’s birthing population ( n = 15,174). Compared to hospital demographics, Study A enrolled 84.1% White, 11.5% Black, and 5.1% Hispanic participants ( p < 0.001 for all comparisons). Study B enrolled 68.9% White, 28.3% Black, and 4.0% Hispanic participants ( p < 0.001 for all comparisons). Study C enrolled 50.3% White ( p = 0.327), 40.2% Black ( p < 0.001), and 9.5% Hispanic participants ( p = 0.082). Recruitment strategies that prioritize accessibility, such as in-person outreach, language support, and greater compensation, were associated with improved representation of racially and ethnically minoritized populations in perinatal research and enhance the relevance of findings to those disproportionately affected by adverse maternal outcomes.