Objective To describe reproductive and lifestyle correlates of surgically confirmed fibroids. Design Prospective Cohort Study Setting The California Teachers Study (CTS), an ongoing prospective study of over 133,000 female teachers and school administrators identified through the California State Teachers Retirement System. Patients CTS cohort members reporting no prior history of fibroids were ascertained prospectively for surgical diagnosis of fibroids using hospital patient discharge records. Main Outcome Measure(s) Multivariable Cox proportional hazards regression methods were used to assess the association of self-reported menstrual, reproductive, and lifestyle characteristics with fibroids, using ages at the start and end of follow-up (in months) to define time on study. Hazard rate ratios, presented as relative risks (RR) with 95% confidence intervals (CI), were estimated. Results The strongest risk factor we identified was African-American race/ethnicity, as compared to non-Latina white women. We observed a reduced risk of fibroids for postmenopausal women in comparison to premenopausal women, but use of hormone replacement therapies (regardless of formulation) were associated with an increased risk. Other risk factors included race, a family history of fibroids, being overweight and drinking alcohol, Smoking and diabetes were associated with a decreased risk of fibroids. Conclusions These observations provide a more detailed epidemiologic profile of women with surgically managed fibroids

Long-term daily use of NSAIDs was not associated with breast cancer risk overall. Ibuprofen use was associated with an increased risk of breast cancer, and long-term daily aspirin use was associated with an increased risk of ER/PR-negative breast cancer. However, it is not clear if the observed association is causal.