A study to determine the efficacy of controlled ovarian hyperstimulation regimen using a gonadotropin releasing hormone agonist versus antagonist in women of advanced reproductive age with varying degrees of oocyte reserve on outcome following in vitro fertilization-embryo transfer.

Purpose: To determine if the use of gonadotropin releasing hormone (GnRH) agonists (a) or antagonists (ant) allow better pregnancy rates when used in controlled ovarian hyperstimulation protocols in women of advanced reproductive age. Furthermore the study aimed to determine if the status of ovarian oocyte reserve has a confounding effect. Materials and Methods: A 12-year retrospective review was performed on all in vitro fertilization-embryo transfer (IVF-ET) cycles in women aged 40-44. Pregnancy rates were determined according to whether a GnRH-a or GnRH-ant was used. The data were also stratified according to normal or low oocyte reserve. Results: There was no significant difference in pregnancy rates according to whether a GnRH-a or GnRH-ant was used in women with normal oocyte reserve. Though a large majority of the women used a GnRH-ant, there was a 9% live pregnancy rate vs 0% in the women using a GnRH-a. Conclusion: Since it is unlikely that a larger study will ever be conducted, it is probably wise to use a GnRH-ant for the controlled ovarian hyperstimulation regimen in women aged 40-44 with diminished oocyte reserve.