Abstract
PURPOSE: To study the association of inhibin B with ovarian response to FSH stimulation, applying either GnRH agonist or antagonist. METHODS: In a prospective randomized controlled trial, 46 patients undergoing COH received either triptorelin (group I, n = 15) or ganirelix (group II, n = 31). Parameters of follicular response and inhibin B serum levels were assessed. RESULTS: Inhibin B before FSH stimulation was significantly lower in group I than group II. The FSH stimulation phase was significantly longer in group I than group II, and the total FSH dose was significantly higher with a comparable number of retrieved oocytes. Day 1 inhibin B in group I, but not group II, was significantly correlated with the number of large ovarian follicles and retrieved oocytes. In group II, but not group I, inhibin B on day 1 was inversely correlated with the daily and total FSH dose as well as FSH stimulation duration. CONCLUSIONS: The association of inhibin B serum levels with parameters of follicular response in COH is different in patients assigned to GnRH agonist vs. antagonist treatment protocols.