High dose Follicle Stimulating Hormone (FSH) and Human Menopausal Gonadotropin (HMG) combined with a single dose of Cetrorelix: can it normalize the response of the poor responder?

Objective: Numerous protocols have been proposed for poor responders undergoing IVF. Several investigators have suggested the use of GnRH antagonists in this patient population. While previous studies have confirmed the efficacy of a single dose of the gonadotropin-releasing hormone (GnRH) antagonist, Cetrorelix, in preventing premature LH surges, the few available data have not shown any benefits with regard to pregnancy rates. The purpose of this study was to compare IVF outcomes in low responders using single dose Cetrorelix with patients using a GnRH agonist long protocol. Design: Retrospective cohort study. Materials and Methods: All patients undergoing IVF treatment from January 2001 to December 2002 using a protocol consisting of high dose FSH/HMG and a single dose of Cetrorelix were compared to an age-matched control group using a GnRH agonist long protocol. Results: Sixty one patients treated with the single dose Cetrorelix protocol were compared with one hundred fifty four patients using the GnRH agonist long protocol. When comparing the Cetrorelix group with the GnRH agonist group, there were no differences in mean age (37.2 ± 4.5 vs. 38.0 ± 3.7), peak estradiol measurements (876.4 ± 447.4 pg/ml vs. 1245 ± 786 pg/ml), and number of embryos transferred (2.4 ± 1.8 vs. 2.5 ± 1.3). The Cetrorelix group showed significantly shorter treatment duration (11.9 ± 2.1 days vs. 13.1± 2.1, P<0.01), and a significantly greater number of mature follicles (8.1 ± 4.1 vs. 5.8± 2.9, P<0.01). A significantly greater amount of combined follicle stimulating hormone (FSH) and human menopausal gonadotropin (HMG) was administered in the Cetrorelix group (5222 ± 1962 IU vs. 1326 ± 1580, P<0.01). The pregnancy rate did not differ significantly between the Cetrorelix and GnRH agonist long protocol groups (26.2% vs. 26.0%, respectively, P-ns). The tolerance of Cetrorelix was good in all patients, with only mild and transitory reactions at the injection site. Conclusion: Peak estradiol measurements and pregnancy rates following IVF treatment in low-responder patients treated with high dose FSH/HMG and single dose Cetrorelix are comparable to standard GnRH agonist long protocol cycles in normal responders. In order to achieve these results, the Cetrorelix group used four times the amount of combined FSH/HMG. High dose FSH/HMG with a single-dose administration of GnRH antagonist could represent the first-choice IVF treatment in this low responder population.