Gonadotropins and combined gonadotropin-releasing hormone agonist--gonadotropins protocols in a randomized prospective study.

A prospective study was designed to compare cycles stimulated by human menopausal gonadotropin (hMG) (group A) with cycles pretreated with gonadotropin-releasing hormone agonist causing pituitary desensitization followed by hMG stimulation (group B). Three hundred two cycles were randomly allocated to each group. Cancellation rate was 27.2% in group A compared with only 3.3% in group B. Significantly less hMG ampules for a shorter period were needed in group A patients. Lower estradiol and higher luteinizing hormone levels were detected in the hMG group. Patients in group B yielded significantly more oocytes and more embryos per retrieval. A significantly higher pregnancy rate per cycle was obtained in group B (27%) as compared with that of group A (13%). Moderate and severe ovarian hyperstimulation syndrome was significantly more frequent in group B than in group A.