Prolonged amenorrhea and oral contraceptives.

Of 106 consecutive women referred for secondary amenorrhea of more than 1 year's duration, 65 were diagnosed as having functional amenorrhea. Of these 65, 29 had amenorrhea directly following discontinuation of oral contraceptives (OC group) and 36 had never used oral contraceptives (NOC group). There was no difference in the incidence of prior menstrual irregularity in either group. Similarly, there was no difference in the resting serum estrone, estradiol, luteinizing hormone, follicle-stimulating hormone, and prolactin levels between the OC and NOC groups. Nor was there a difference between the OC and NOC groups in response to medroxyprogesterone acetate, clomiphene citrate, or luteinizing hormone-releasing factor. Of 106 patients, 17 were proven to have prolactinomas. Eight patients had a prior history of OC use, whereas nine did not. With the exception of elevated serum prolactin levels, there were no significant differences in biochemical tests or history of oral contraceptive use between the prolactinoma group and patients with prolonged "functional" amenorrhea (OC plus NOC groups). The lack of historical or biochemical difference between the OC and NOC subjects indicates homogeneity between groups, and does not support the existence of a "postpill" syndrome.