Ovarian hyperstimulation caused by gonadotroph adenoma secreting follicle-stimulating hormone 28-year-old woman

Ovarian hyperstimulation caused by a gonadotroph adenoma in premenopausal w omen has been described only twice before this report. A 28-yr-old woman pr esented with menstrual disturbances and pelvic pains that began after stopp ing the use of contraceptive pills. Transvaginal ultrasound revealed enlarg ed ovaries with multiple cysts. The patient had elevated serum estradiol (u p to 2900 pmol/L; normal, 80-300 pmol/L in the follicular phase) and inhibi n (6.4 kU/L; normal, 0.5-2.5 kU/L) levels. Serum LH was appropriately suppr essed (0.6 IU/L), but serum FSH varied from 4.9-8.1 IU/L. Both gonadotropin s as well as the free a-subunit showed a paradoxical response to the stimul us by TRH. A nuclear magnetic resonance study unraveled a pituitary tumor, 12-14 mm in diameter, extending up to the suprasellar cistern. After pituit ary surgery, all hormone values normalized, and the patient resumed regular ovulatory cycles. In immunostaining, 20-30% of the cells of the tumor stai ned positively for FSH beta. We conclude that a gonadotropin-producing aden oma must be considered in the differential diagnosis of a patient presentin g with large multicystic ovaries and high estradiol levels in the absence o f exogenous gonadotropins.