Oral contraceptive use and fibrocystic breast disease among pre- and postmenopausal women.

The association between use of oral contraceptives and fibrocystic breast disease was assessed among women aged 20-74 years in a hospital-based case-control study conducted between November 1979 and November 1981 in Connecticut. The study groups comprised 633 women with biopsy-proven fibrocystic breast disease and 1,062 controls who had been admitted, as inpatients or outpatients, to general surgical services. For the premenopausal women, there was no evidence that long-term use of oral contraceptives was associated with a decreased frequency of fibrocystic breast disease among either current or past users. For the postmenopausal women, previous oral contraceptive exposure was associated with an increased occurrence of cystic disease. These findings contradict previous investigations reporting a negative association between oral contraceptive use and the development of fibrocystic breast disease.