A PROSPECTIVE RANDOMIZED SINGLE-BLIND COMPARATIVE TRIAL OF NAFARELIN ACETATE WITH BUSERELIN IN LONG-PROTOCOL GONADOTROPIN-RELEASING-HORMONEANALOG CONTROLLED IN-VITRO FERTILIZATION CYCLES

The use of gonadotrophin-releasing hormone (GnRH) agonists to control ovulation induction cycles for in-vitro fertilization (IVF) has been s hown to increase the pregnancy rate and live birth rate compared with non-analogue cycles. Different formulations of GnRH agonist are availa ble with different routes and frequencies of administration. In this p rospective study, the efficacy and safety of intranasal nafarelin and buserelin as adjunctive therapy during IVF were assessed. A total of 2 40 female patients were recruited to the study and in the first phase patients were randomized to receive either intranasal nafarelin 200 mu g twice daily or buserelin 200 mu g five times daily. In the second p hase, patients received either nafarelin 400 mu g twice daily or buser elin 200 mu g five times daily. Nafarelin 400 mu g and buserelin 200 m u g both produced clinical pregnancy rates of 31% per recruit and 39% per embryo transfer. The rates for nafarelin 200 mu g were 23 and 37% respectively. There was no statistically significant difference in pre gnancy rates, by either drug or dosage. The time taken for pituitary d own-regulation to be achieved was significantly longer on nafarelin 20 0 mu g than on either nafarelin 400 mu g or buserelin. The total numbe r of days stimulation with human menopausal gonadotrophin required to reach criteria for human chorionic gonadotrophin (HCG) administration was significantly longer on buserelin than on either dose of nafarelin . Median serum oestradiol concentrations on the day of HCG administrat ion were significantly higher on either dose of nafarelin than on buse relin.