Menstrual pain and epithelial ovarian cancer risk

Menstrual pain is associated with increased production of inflammatory molecules, such as prostaglandins. Inflammation is involved in pathogenesis of several cancers, including ovarian cancer. In this study, we examined the association between menstrual pain and risk of ovarian cancer. We conducted a case-control study with 2,028 cases of epithelial ovarian cancer and 2,091 age- and study center-matched controls. Women were asked to report the severity of menstrual pain during their twenties and thirties, when not using oral contraceptives or breastfeeding. We used an unconditional logistic regression to evaluate the association between menstrual pain and epithelial ovarian cancer risk overall, and polytomous logistic regression to evaluate whether the association differed across tumor subtypes. Risk of ovarian cancer was increased in women with moderate (OR 1.22, 95 % CI 1.05-1.42) and severe pain (OR 1.34, 95 % CI 1.09-1.65) compared to women with no or mild pain during menstrual period. The association differed by histologic subtypes, with significant associations for severe pain with endometrioid (OR 1.64, 95 % CI 1.15-2.34) and clear cell tumors (OR 1.91, 95 % CI 1.11-3.28). Our data suggest that moderate and severe pain during menstrual period are associated with increased risk of epithelial ovarian cancer. Due to high prevalence of menstrual pain in women of reproductive age, this observation warrants further studies.