A PROSPECTIVE RANDOMIZED SINGLE-BLIND COMPARATIVE TRIAL OF NAFARELIN ACETATE WITH BUSERELIN IN LONG-PROTOCOL GONADOTROPIN-RELEASING-HORMONE ANALOG 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 shown to increase the pregnancy rate and live birth rate compared with non-analogue cycles. Different formulations of GnRH agonist are available with different routes and frequencies of administration. In this prospective study, the efficacy and safety of intranasal nafarelin and buserelin as adjunctive therapy during IVF were assessed. A total of 240 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 phase, patients received either nafarelin 400 mu g twice daily or buserelin 200 mu g five times daily. Nafarelin 400 mu g and buserelin 200 mu 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 pregnancy rates, by either drug or dosage. The time taken for pituitary down-regulation to be achieved was significantly longer on nafarelin 200 mu g than on either nafarelin 400 mu g or buserelin. The total number 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 administration were significantly higher on either dose of nafarelin than on buserelin.