Tubal sterilization and risk of cancer of the endometrium

Objective. Surgical sterilization is a common method of contraception among U.S. women, Most surgical sterilizations are tubal ligations, but few stud ies have investigated their potential impact on endometrial cancer risk, Methods. A case-control study included 405 women diagnosed with endometrial cancer at 5 U.S. medical centers between 1987 and 1990 and 297 age-, race- , and location-matched controls who were identified by random-digit-dialing . Questionnaires ascertained information on tubal sterilization, and logist ic regression models generated odds ratios (ORs) to estimate relative risk. Results. The OR and 95% confidence interval for tubal sterilization, which was reported by 47 cases and 40 controls, was 0.9 (0.6-1.4) before adjustme nt and 1.4 (0.8-2.4) after adjustment for age, parity, and oral contracepti ve use. Age at surgery, years since surgery, or calendar years of surgery w ere not associated with endometrial cancer, and associations did not vary a ccording to parity or stage of disease at diagnosis. Conclusions. Tubal sterilization is not substantially associated with endom etrial cancer. (C) 2000 Academic Press.