The significance of delayed suppression using buserelin acetate and recombinant follicle-stimulating hormone in a long protocol in vitro fertilization program

Objective: To determine whether the time taken to achieve ovarian suppressi on has an impact on ovarian responsiveness and the outcome of IVF-ET. Design: Retrospective analysis. Setting: An assisted reproduction unit at a university center. Patient(s): Patients undergoing a long protocol of IVF-ET that included bus erelin acetate therapy initiated on day 2 of the cycle and recombinant FSH. Intervention(s): Patients were divided into two groups according to the dur ation of buserelin acetate therapy required to achieve pituitary and ovaria n suppression (group 1 = 2 weeks, n = 172; group 2 = greater than or equal to 3 weeks, n = 337). Main Outcome Measure(s): Number of recombinant FSH ampules administered, du ration of ovarian stimulation (days), ovarian response, and IVF outcome. Result(s): The patients in group 2 had lower mean E-2 levels after 5 days a nd 9 days of stimulation than the patients in group 1. The number of recomb inant FSH ampules administered and the number of days of stimulation requir ed were higher in group 2 than in group 1. These differences were prominent in the subgroups of older patients (greater than or equal to 36 years) and patients who had no evidence of polycystic ovaries on ultrasound examinati on. The number of oocytes retrieved and fertilized, the cancelation rate, a nd the pregnancy rate were similar in the two groups. Conclusion(s): Prolonged administration of a GnRH agonist to achieve suppre ssion leads to a reduced ovarian response, particularly in women greater th an or equal to 36 years of age, but does not affect the success rate of IVF -ET. (Fertil Steril(R) 2000;73:325-9. (C)2000 by American Society for Repro ductive Medicine.).