Exogenous gonadotropin requirements are increased in leuprolide suppressed women undergoing ovarian stimulation.

We used a subcutaneously administered GnRHa for 21 to 26 days prior to menotropin stimulation, to suppress endogenous LH surges in four patients participating in IVF. GnRHa-pretreated cycles were compared with previous menotropin treatment cycles. Endogenous LH surges were successfully suppressed in all patients. Peak E2 levels and ultrasonographic parameters of follicular development were comparable in the two treatment groups. Exogenous gonadotropin requirements were increased 2- to 4-fold in GnRHa pretreated cycles (P less than 0.05). Ovum recovery rates were not improved by adjuvant LA. These studies indicate that there was an increased ovarian requirement for exogenous gonadotropins as a result of GnRHa therapy. It has to be considered that this may be a direct effect of GnRHa upon the ovary. Alternatively, the absence of endogenous pituitary support in GnRHa-treated patients may account for the increased gonadotropin requirement. Finally, it is possible that this effect is indigenous to this select patient population of poor responders to menotropin stimulation, or to a specific effect of subcutaneously (as opposed to intranasally) administered GnRHa on the ovary. Further studies are needed to clarify the extent to which any or all of these postulated mechanisms may be influencing ovarian response to exogenous gonadotropins after subcutaneous GnRHa pretreatment.