Occupational risk factors for endometriosis in a cohort of flight attendants

This study aimed to compare odds of endometriosis in a cohort of flight attendants against a comparison group of teachers and investigate occupational risk factors for endometriosis among flight attendants. The authors included 1945 flight attendants and 236 teachers aged 18-45 years. Laparoscopically confirmed endometriosis was self-reported via telephone interview, and flight records were retrieved from airlines to obtain work schedules and assess exposures for flight attendants. We used proportional odds regression to estimate adjusted odds ratios (ORadj) and 95% confidence intervals (95% CI) for associations between exposures and endometriosis, adjusting for potential confounders. Among flight attendants, there were no clear trends between estimated cosmic radiation, circadian disruption, or ergonomic exposures and endometriosis. Greater number of flight segments (non-stop flights between two cities) per year was associated with endometriosis (ORadj 2.2, 1.1-4.2 for highest versus lowest quartile, P trend= 0.02) but block hours (taxi plus flight time) per year was not (ORadj 1.2, 95% CI 0.6-2.2 for highest versus lowest quartile, P trend=0.38).