Histologic changes associated with oral contraceptive usage.

Histologic changes associated with oral contraceptive usage have been described in the cervix, endometrium, myometrium, ovaries, breast, liver and blood vessels. Several types of lesions have been shown to occur frequently in women taking hormonal contraceptives. These include: (1) microglandular hyperplasia of the cervix; (2) endometrial gland regression and stromal decidualization (combination agents); (3) ovarian size reduction associated with cortical fibrosis, suppression of follicle growth and decreased luteinization; and (4) endothelial proliferation and subendothelial fibrosis in blood vessels generally. In addition, cases have begun to be reported in the past few years of adenocarcinoma of the cervix, carcinoma of the endometrium and tumors of the liver. Atypical but benign changes have also been described in myometrium and breast tissue, and neoplastic lesions in animals given hormonal contraceptive agents have been reported in these sites as well as in the ovary. The various types of changes that occur, both benign and malignant, correlate with known actions of the sex steroids.