Ovarian hyperstimulation syndrome caused by pituitary gonadotroph adenoma secreting follicle-stimulating hormone

BACKGROUND: We report a highly exceptional case in which a gonadotroph adenoma was diagnosed in a patient with normal follicle-stimulating hormone (FSH) levels. CASE: A 30-year-old woman with a gonadotroph adenoma presented with hyperstimulation syndrome and normal FSH levels. After treatment of her adenoma she had regular menstrual cycles and subsequently conceived. CONCLUSION: Ovarian hyperstimulation caused by a gonadotroph adenoma in a premenopausal woman with normal FSH levels is extremely rare. However, we propose that gonadotroph adenomas be considered in the differential diagnosis of patients who have this constellation of abnormalities.