Significance of an abnormal response during pituitary desensitization in an in vitro fertilization and embryo transfer program

Purpose: Our purpose was to evaluate the IVF-ET outcome in patients who did not achieve timely pituitary-ovarian suppression following long-protocol GnRH agonist (GnRH-a) administration. Methods: A retrospective analysis was done on 96 IVF treatment cycles characterized by a delayed response (DR) to long-protocol GnRH-a treatment. The study included those patients who either achieved ovarian suppression (E₂ 110 pM) despite an elevated LH level (group DR-A) or had pituitary desensitization (LH 1.5 IU/L) without ovarian suppression (group DR-B) on day 12 of GnRH-a treatment but needed an extended course of GnRH-a treatment to achieve complete suppression. These patients had gonadotropin stimulation either from day 12, despite an elevated level of LH (subgroup DR-A1; n=13) or elevated E₂ levels (subgroup DR-B1; n=9), or after achieving a complete hypogonadotropic-hypopgonadal state following an extended course of GnRH-a treatment subgroups DR-A2 (n=46) and DR-B2 (n=28)]. The outcome was compared with that of 88 cycles of normal responders (group NR) who had pituitary-ovarian suppression by day 12 of GnRH-a administration. Results: Ovarian response and pregnancy rates in subgroups DR-A1 and DR-A2 were statistically not different and comparable to those in the NR group. In subgroups DR-B1 and DR-B2, E₂ response and rates of oocyte retrieval and pregnancy were significantly lower than those in the other groups, but fertilization and cleavage rates were similar. The requirement of gonadotropin for ovarian stimulation was comparatively higher in subgroup DR-A2 and both DR-B subgroups. Conclusions: There was no treatment cancellation in group NR and both DR-A subgroups, but 22% of the cycles in DR-B1 and 14% of the cycles in DR-B2 were canceled due to poor ovarian response. It therefore appears that during long-protocol pituitary desensitization, the post-GnRH-a level of serum E₂, rather than LH, better predicts IVF-ET outcome.Presented in part at the XIth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995, Vienna, Austria.