Determination of the efficiency of controlled ovarian hyperstimulation in the gonadotropin-releasing hormone agonist-suppression cycle using the initial follicle count during gonadotropin stimulation

Purpose: Our purpose was to evaluate the relationship between the initial follicle count during gonadotropin stimulation after gonadotropin-releasing hormone (GnRH) agonist suppression and the efficiency of controlled ovarian hyperstimulation (COH) in patients receiving treatment with assisted reproductive technologies (ARTs). Methods: A total of 338 COH procedures in 291 couples was performed with cycles that reached the stage of oocyte retrieval. The ovarian antral follicle number was measured using transvaginal ultrasonography at the folliculometry during gonadotropin stimulation by GnRH agonist suppression in patients undergoing ARTs. Controlled ovarian hyperstimulation was accomplished using GnRH agonist down-regulation combined with FSH and menotropin stimulation. The characteristics of oocytes after retrieval and embryos after in vitro culture and the pregnancy rates were assessed. Results: The procedures performed included 195 ET cycles, 129 TET cycles, and 14 incomplete cycles. The treatment cycles were divided into four categories according to the antral follicle number (i.e., ≤5,6-10, 11-15, and ≥16) at the first folliculometry to evaluate the influence of various factors. The antral follicle count correlated significantly with the patient age, dosage of gonadotropins, serum estradiol concentration, number of antral follicles (≥13 mm) while receiving hCG injections, number of oocytes retrieved, and, later, number of embryos transferred. There was a trend toward an increasing number of pregnancies per cycle as the number of antral follicles increased (14.7, 26.5, 44, and 45%, respectively). Conclusions: We were able to predict the efficiency of COH and outcome of ARTs based on the follicle count during the first folliculometry during gonadotropin stimulation after GnRH agonist suppression. The results of the folliculometry significantly predicted the ovarian response to COH and the outcome of ARTs in the current treatment cycle.