Epidemiology of Benign Breast Lesions: Lack of Association with Oral Contraceptive Use

Women with benign breast lesions were compared with matched hospital controls to determine epidemiologic features and use of oral contraceptives and estrogens. There were 306 patients with cystic disease and related conditions, 71 with fibroadenoma and 39 with miscellaneous other lesions. In the cystic-disease group there was a deficit of postmenopausal women and women whose first pregnancy was under age 25. A history of use of oral contraceptives or estrogens was given no more frequently by patients with cystic disease and fibroadenoma than by their respective controls. Fewer patients with cystic disease (14) than controls (34) had used oral contraceptives for more than one year. These findings imply that use of oral contraceptives or estrogens has no role in the occurrence of benign breast neoplasms. The reproductive histories of patients with benign and malignant breast neoplasms appear similar in some respects.