Treatment-related amenorrhea in a modern, prospective cohort study of young women with breast cancer

Abstract Young women with breast cancer experience unique treatment and survivorship issues centering on treatment-related amenorrhea (TRA), including fertility preservation and management of ovarian function as endocrine therapy. The Young Women’s Breast Cancer Study (YWS) is a multi-center, prospective cohort study of women diagnosed at age ≤40, enrolled from 2006 to 2016. Menstrual outcomes were self-reported on serial surveys. We evaluated factors associated with TRA using logistic regression. One year post-diagnosis, 286/789 (36.2%) experienced TRA, yet most resumed menses (2-year TRA: 120/699; 17.2%). Features associated with 1-year TRA included older age (OR ≤30vs36-40 = 0.29 (0.17–0.48), OR31-35vs36-40 = 0.67 (0.46–0.94), p = 0.02); normal body mass index (BMI) (OR ≥25vs18.5-24. =0.59 (0.41–0.83), p