Evaluation of ovarian and adrenal sources of androgens in women with polycystic ovary syndrome: Dexamethasone and GnRH-agonist administration

Ovarian and adrenal production of androgens was evaluated in 18 patients with polycystic ovary syndrome (PCOS) by administrating a combination of short-term dexamethasone (DEX) and long-term gonadotropin-releasing hormone agonist (GnRH-A). At day 6 of the cycle, blood samples were collected at 7 A.M. (basal) and 11 P.M. At midnight, 2 mg DEX was given orally, and blood samples were collected at 7 A.M. the following day (DEX 1). Blood samples were obtained for 6 weeks at the same time after administration of a potent GnRH-A (400 μg/day given subcutaneously). Eight normal subjects served as controls. The amounts of androgens and 17-hydroxyprogesterone (17-OHP) suppressed by using DEX (adrenal-source suppression) and GnRH-A (ovarian- source suppression) were greater in PCOS patients than in controls. We differentiated PCOS patients as having a normal or an exaggerated response to DEX or GnRH-A administration; threshold values were considered average +2SD of the suppressed androgen amounts of controls. Three patients had an exaggerated response to GnRH-A treatment for androstenedione, testosterone and 17-OHP, while DEX inhibition was similar to controls. The remaining 15 patients had an exaggerated response to DEX for all three androgens; seven also had an exaggerated response to GnRH-A. Thus, the combination of GnRH-A and DEX permitted us to selectively study and identify adrenal and ovarian sources of hyperandrogenemia.