Sexual Orientation-Related Disparities in Neonatal Outcomes.

Objective: To evaluate whether disparities exist in adverse neonatal outcomes among the offspring of lesbian, gay, bisexual, and other sexually minoritized (LGB+) birthing people.

Methods: We used longitudinal data from 1995 to 2017 from the Nurses' Health Study II, a cohort of nurses across the United States. We restricted analyses to those who reported live births (N=70,642) in the 2001 or 2009 lifetime pregnancy questionnaires. Participants were asked about sexual orientation identity (current and past) and same-sex attractions and partners. We examined preterm birth, low birth weight, and macrosomia among 1) completely heterosexual; 2) heterosexual with past same-sex attractions, partners, or identity; 3) mostly heterosexual; 4) bisexual; and 5) lesbian or gay participants. We used log-binomial models to estimate risk ratios for each outcome and weighted generalized estimating equations to account for multiple pregnancies per person over time and informative cluster sizes.

Results: Compared with completely heterosexual participants, offspring born to parents in all LGB+ groups combined (groups 2-5) had higher estimated risks of preterm birth (risk ratio 1.22, 95% CI, 1.15-1.30) and low birth weight (1.27, 95% CI, 1.15-1.40) but not macrosomia (0.98, 95% CI, 0.94-1.02). In the subgroup analysis, risk ratios were statistically significant for heterosexual participants with past same-sex attractions, partners, or identity (preterm birth 1.25, 95% CI, 1.13-1.37; low birth weight 1.32, 95% CI, 1.18-1.47). Risk ratios were elevated but not statistically significant for lesbian or gay participants (preterm birth 1.37, 95% CI, 0.98-1.93; low birth weight 1.46, 95% CI, 0.96-2.21) and bisexual participants (preterm birth 1.29, 95% CI, 0.85-1.93; low birth weight 1.24, 95% CI, 0.74-2.08).

Conclusion: The offspring of LGB+ birthing people experience adverse neonatal outcomes, specifically preterm birth and low birth weight. These findings highlight the need to better understand health risks, social inequities, and health care experiences that drive these adverse outcomes.