Oral contraceptives and benign ovarian tumors

Whether use of combined oral contraceptives (OC) protects against benign ov arian tumors is unknown. A case-control study of pathologically confirmed b enign ovarian tumors was conducted in the New York City area and included c ases diagnosed from January 1, 1992, to December 31, 1993, and controls ide ntified by random digit dialing. There were 196 cases with serous adenomas, 176 with teratomas, 311 with endometriomas, and 65 with mucinous adenomas. Interview data were used to determine contraceptive use. Ever use of OC wa s associated with a decreased risk of these benign tumors (age- and hospita l-adjusted odds ratio = 0.79, 95% confidence interval: 0.60, 1.05). In hist ologic subgroup analyses, the risk of ovarian tumors was reduced for both c urrent and past OC users. Among tumor subtypes, the risk reduction was grea test for women who had endometriotic lesions. The risk reduction also was g reater for women who had used OC for more than 24 months. Protection agains t benign ovarian tumors may be an additional noncontraceptive benefit of OC use.