Infertility and risk of fatal ovarian cancer in a prospective cohort of USwomen

Objectives: It is difficult to separate the possible role of fertility drug s from underlying infertility as risk factors for ovarian cancer. The prese nt study examined the relationship between self-reported infertility and de ath from ovarian cancer among married women unlikely to have been exposured to fertility drugs. Methods: Women were selected for study from the 676,526 female participants in Cancer Prevention Study II (CPS-II). After twelve years of follow-up, 7 97 deaths from ovarian cancer were observed among women with no prior histo ry of cancer or hysterectomy and 40 years of age or older in 1967 when ovul atory stimulants were approved in the United States. Cox proportional hazar ds modeling was used to compute rate ratios (RRs) and to adjust for other p otential risk factors. Results: Overall, self-reported infertility was not significantly associate d with ovarian cancer mortality (adjusted rate ratio (RR) = 1.1, 95 percent confidence interval (CI) = 0.9-1.3). Ovarian cancer death rates among null igravid women with self-reported infertility, however, were 40 percent high er than for nulligravid women who never tried to become pregnant (RR = 1.4, 95 percent CI = 0.9-2.4). Multigravid women who reported infertility probl ems were not at increased risk. Conclusions: These results suggest that infertility itself, without concomi tant exposure to fertility drugs, may increase risk of fatal ovarian cancer among nulligravid women.