Migraine and invasive epithelial ovarian cancer risk in the Nurses' Health Study II and the Women's Health Study.

Migraine is a common primary headache disorder, which predominantly impacts women. Recently, migraine has been hypothesized to be associated with hormonally related cancers; however, the potential association between migraine and ovarian cancer has not been studied. Therefore, we evaluated the association between migraine and invasive epithelial ovarian cancer risk in two prospective cohorts, the Nurses' Health Study II (NHSII) and the Women's Health Study (WHS). Our prospective analysis included 113,124 NHSII participants aged 25-42 at study baseline as well as 33,490 participants in the WHS who were 45 years or older at study entry. We used Cox proportional hazards models to estimate the hazard ratios (HR) and 95% confidence intervals (CIs) for the association between migraine and ovarian cancer risk in each cohort. In secondary analyses, we stratified by age and menopausal status. After adjusting for potential covariates, there was no statistically significant association between migraine and ovarian cancer risk in either the NHSII (HR = 1.29, 95%CI: 0.96, 1.74) or the WHS (HR = 0.60, 95%CI: 0.34, 1.06). In stratified analysis in the NHSII, there was a statistically significant positive association between migraine and ovarian cancer risk among women <45 years of age (HR = 1.76, 95%CI: 1.01, 3.07). We did not observe a clear association between migraine and ovarian cancer risk in two large prospective cohort studies.