Health Disparities
Sexual orientation disparities in adverse pregnancy outcomes Payal Chakraborty* Payal Chakraborty Ellis Schroeder Colleen A. Reynolds Sarah McKetta Juno Obedin-Maliver S. Bryn Austin Bethany Everett Sebastien Haneuse Brittany M. Charlton
Background: Sexual minority (SM) individuals have health profiles—e.g., health behaviors; limited resources due to structural, interpersonal, and individual stigma—that may place them at higher risk for adverse pregnancy outcomes (APOs), yet little research has examined sexual orientation disparities in APOs.
Methods: We used pregnancy data from the Nurses’ Health Study 3, an ongoing cohort of nurses and nursing students in the US/Canada. Pregnancies occurred from 1978–2023. We analyzed 6 self-reported APOs: preterm birth (PTB), low birthweight (LBW), and macrosomia (MAC) among live births (N=25,877) and gestational hypertension (gHTN), gestational diabetes (GDM), and preeclampsia (PRE-E) among pregnancies ≥20 weeks (N=26,176). We examined disparities among 5 sexual orientation groups: completely heterosexual (reference), heterosexual with same-sex experience; mostly heterosexual; bisexual; and lesbian. We used log-binomial models to estimate risk ratios (RRs) fit via weighted generalized estimating equations to account for multiple pregnancies per person and informative cluster sizes.
Results: Compared to pregnancies to completely heterosexual participants, those of SM groups combined had higher risks of GDM (RR[95%CI]: 1.15[1.00–1.34]), gHTN (1.33[1.18–1.50]), and PRE-E (1.23[1.07–1.42]); no significant differences were observed for PTB, LBW, and MAC. Pregnancies to heterosexual participants with same-sex experience and mostly heterosexual participants had a higher risk of gHTN (1.34[1.08–1.66]; 1.30[1.12–1.51]), respectively) and PRE-E (1.40[1.09–1.79]; 1.20[1.00–1.44]) and lesbian participants had a higher risk of gHTN (1.68[1.11–2.52]). Bisexual and lesbian participants had RRs with high magnitudes for most APOs.
Conclusions: SM individuals experience disparities in many APOs, and disparities differ by SM subgroup. Elucidating the pathways to reduce disparities (e.g., structural barriers, health care needs) is critical for achieving reproductive health equity.
