Reducing the dose of gonadotrophin-releasing hormone agonist on starting ovarian stimulation: effect on ovarian response and in-vitro fertilization outcome

The aim of this study was to examine if lowering the dose of gonadotrophin-releasing hormone agonist (GnRHa) on starting ovarian stimulation could be beneficial in in-vitro fertilization (IVF) programmes. A total of 64 normally ovulating patients entering an IVF programme were randomized to receive GnRHa (nafarelin acetate/Synarel) as an intranasal spray commencing in the midluteal phase, either at a dosage of 200 microg three times daily until the day of human chorionic gonadotrophin (HCG) administration, or to be reduced to 200 microg twice daily as ovarian stimulation was initiated. Patients in both groups were below 35 years with a body mass index below 30. All patients received three ampoules of Metrodin HP per day. Blood samples were taken on the day of HCG administration to measure luteinizing hormone (LH), oestradiol, and progesterone. LH and oestradiol were found to be significantly higher in the lower Synarel dose group. Our results show that reducing the GnRHa dose during ovarian stimulation in IVF might be beneficial in terms of significantly more oocytes recovered, and significantly greater number of embryos available for transfer and freezing, with no incidence of premature luteinization.