Tubal ligation and the risk of ovarian carcinoma.

To assess the relationship of tubal ligation and risk of ovarian carcinoma, we conducted a case-control, retrospective analysis of 300 ovarian carcinoma cases and 606 nonmalignant disease controls, seen between 1982 and 1988 at Roswell Park Cancer Institute, Buffalo, New York. Women who had a tubal ligation had reduced risk for the development of ovarian cancer. This relative risk was 0.52, with a 95% confidence interval 0.31 to 0.85 (p = 0.0076). Controls were matched by age. Multivariate analysis adjusted for socioeconomic level, marital status, parity, age at first pregnancy, menarche age, menopause age, irregular menses, breast-feeding duration, body habitus, and oral contraceptive use. Suggested explanations for this observation are offered.