Sexual minority individuals face higher cesarean risks

December 11, 2025-- Individuals who identify as a sexual minority face higher risks of primary Cesarean birth compared with their completely heterosexual peers, according to a new study from Columbia University Mailman School of Public Health. Risks varied substantially across sexual-orientation subgroups, with the largest increase observed among a rarely examined group: people who identify as heterosexual but report prior same-sex experience. The findings are published in the Lancet Regional Health.

Disparities were especially pronounced when labor was induced.

“Very little national data captures both detailed sexual-orientation measures and birth outcomes,” said Sarah McKetta, MD, PhD, assistant professor of Epidemiology at Columbia Mailman School. “By combining three rich national surveys, we were able to identify elevated risks among subgroups—particularly heterosexual participants with same-sex experience—who have been largely absent from perinatal research. We urge researchers to incorporate detailed orientation and gender-identity measures in future longitudinal studies to better understand these patterns.”

Researchers analyzed pregnancy-level data from three large, long-running U.S. cohort studies: Nurses’ Health Study 2 and 3 and the Growing Up Today Study. Together these cohorts span people born between 1947 and 1997 who were surveyed every one to three years.

Sexual minority (SM) pregnancies represented 14 percent of all pregnancies in the sample, though less than 1 percent came from participants identifying as lesbian or gay. Overall, SM participants had 7 percent higher odds of a primary Cesarean birth compared with completely heterosexual participants. SM pregnancies also occurred disproportionately among racially minoritized individuals.

The study additionally found higher rates of induced labor among sexual minority participants. “This is notable,” McKetta said, “because the Cesarean disparity was greatest following induction—raising concerns about potential differences, including provider bias, in decision-making around interventions.”

Cesarean births account for more than 1.1 million surgeries each year in the U.S. and represent 26 percent of low-risk births. Although often lifesaving, Cesareans are widely considered overused, contributing to higher healthcare costs and increased maternal morbidity.

“Future research should examine individual, interpersonal, and structural factors contributing to these disparities so we can design interventions that reduce them,” McKetta said. “Clinicians should also be mindful of unintentionally lowering the threshold for moving from induction to Cesarean among sexual minority patients, which may worsen existing inequities. Reducing unwarranted Cesareans in this population will improve health outcomes and support national goals to decrease primary Cesarean births.”

Co-authors include Kodiak R. S. Soled (first author), Payal Chakraborty, Colleen A. Reynolds, Bethany G. Everett, Daphna Stroumsa, Sebastien Haneuse, S. Bryn Austin, Jorge E. Chavarro, Aimee K. Huang, and Brittany M. Charlton across Harvard Pilgrim Health Care Institute, Harvard T.H. Chan School of Public Health, University of Utah, University of Michigan, Boston Children’s Hospital, Brigham and Women’s Hospital, and Massachusetts General Hospital.

The study was supported by NIH grants U01CA176726, U01HL145386, R01MD015256, T32HL098048, T32CA009001, R01MH112384, K23MD016950, T32CA057711, P30HS029762, K99HD114852, and K99AA031316; the Thomas O. Pyle Fellowship; the William T. Grant Foundation, and the Mongan Institute Director’s Fund.

Columbia University Mailman School of Public Health

Founded in 1922, the Columbia University Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Columbia Mailman School is the third largest recipient of NIH grants among schools of public health. Its nearly 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change and health, and public health preparedness. It is a leader in public health education with more than 1,300 graduate students from 55 nations pursuing a variety of master’s and doctoral degree programs. The Columbia Mailman School is also home to numerous world-renowned research centers, including ICAP and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.