INFERTILITY, FERTILITY DRUGS, AND INVASIVE OVARIAN-CANCER - A CASE-CONTROL STUDY

Objective: To assess the risk of invasive ovarian cancer among inferti le women treated with fertility drugs. Design: A case-control study. S etting: Nationwide data based on public registers. Patient(s): All Dan ish women (below the age of 60 years) with ovarian cancer during the p eriod from 1989 to 1994 and twice the number of age-matched population controls. Included in the analysis were 684 cases and 1,721 controls. Main Outcome Measure(s): Influence of parity, infertility, and fertil ity drugs on the risk of ovarian cancer after multivariate confounder control. Risk measure(s): odds ratios (OR) with 95% confidence interva ls. Result(s): Nulliparous women had an increased risk of ovarian canc er compared with parous women: OR 1.5 to 2.0. Infertile, nontreated nu lliparous women had an OR of 2.7 (1.3 to 5.5) compared with noninferti le nulliparous women. The OR of ovarian cancer among treated nulliparo us women was 0.8 (0.4 to 2.0) and among treated parous 0.6 (0.2 to 1.3 ), compared with nontreated nulliparous and parous infertile women, re spectively. Conclusion(s): Nulliparity implies a 1.5- to 2-fold increa sed risk of ovarian cancer. Infertility without medical treatment amon g these women increased the risk further. Among parous as well as null iparous women, treatment with fertility drugs did not increase the ova rian cancer risk compared with nontreated infertile women. (C) 1997 by American Society for Reproductive Medicine.