The purpose of this study was to determine the extent of oral contraceptive (OC) exposure of women with secondary amenorrhea of hypothalamic-pituitary etiology. In 93 of 126 women with secondary amenorrhea sufficient data were obtained regarding menstrual history and OC exposure: 26 patients had evidence of a prolactinoma, an additional 26 patients had idiopathic hyperprolactinemia without evidence of a pituitary tumor, and 41 had "pure" dysfunction hypothalamic-pituitary amenorrhea. After stratification by age at diagnosis and parity the estimated odds ratio for past oral contraceptive usage showed no differences among the three groups (odds ratios between 0.74 and 1.48). Using the chi-square test the proportion of subjects who had regular menses before oral contraceptive intake and developed anovulation immediately after discontinuance ("post pill amenorrhea") in the three groups also showed no difference (x2 = 0.60, P = 0.74). These data indicate that non-ovulatory patients are likely to have been exposed to OC, and do not indicate that patients with prolactinomas differ in the extent of their OC exposure from other specified groups of patients with secondary.