ORIGINAL ARTICLE Reproductive epidemiology Severe teenage acne and risk of endometriosis

study question: Is there a relationship between severe teenage acne and endometriosis? summaryanswer: Endometriosis is positively associated with severe teenage acne. what is known already: No studies have specifically explored a possible association between severe acne in adolescence and risk of endometriosis. study design, size, duration: This prospective cohort study used data collected from88 623 female nurses from September 1989 to June 2009 as part of the Nurses ’ Health Study II (NHS II) cohort. participants/materials, setting, methods: Regressionmodels were used to calculate hazard ratios (HRs) and confidence intervals (CIs) for endometriosis among women with and without severe teenage acne. Multivariate models were adjusted for established risk factors of endometriosis. main results and the role of chance: A total of 4 382 laparoscopically confirmed endometriosis cases were documented during 1 132 272 woman-years of follow-up. Compared with women without a history of severe teenage acne, women who had severe teenage acne had a 20 % increased risk of endometriosis (HR 1.20, 95 % CI: 1.08–1.32). The association was not affected by adjusting for use of tetracycline or isotretinoin.