Received April 23, 1999
Accepted October 16, 1999

A prospective study was conducted to compare the efficiency of ovarian blockade with leuprolide acetate versus nafarelinin a population whose indication for assisted reproduction was the male factor. 238 patients were assigned at random to two types of treatment: Group I, nafarelin, 200µg by the nasal route twice a day; and Group II, leuprolide acetate, 0.5 mg by the subcutaneous route once a day. All patients received a fixed dose of FSH for 7days and on the 8th day of stimulation the doses started to be adapted according to ovarian response. Patients age did not differ(p=0.93) between group I(34.1±3.79) and group II(34±4.64). The number of oocytes retrieved at group I(10.5±5.93) was also similar (p=0.57) from the group II( 1 0.2± 6.36). ln addition, there is no difference(p=0.58) of the number of oocytes retrieved at metaphase II between the group I(8.2±4.6 1 ) and the group II(7.9±5.2). Fertilization rates and embryos scores were similar (p=0.8 1 and p=0.25, respectively) between group I(67.5%±21.3 and 34.4%±14.4) and group II(68.1%±23 and 32.2%±1 4.7, respectively). On the other hand, pregnancy rates per punction and per embryo transfer and implantation rates between group I(30.2%, 31.3%, 16.2%, respectively) and the group II (24.4%, 25.2 %, 12.6 %, respectively) were also similar (p=0.38, p=0.37 and p=0.22, respectively). Thus far, the data do not demonstrate significant differences in ovarian blockade with leuprolide versus nafarelin in patients whose indication for assisted reproduction was the male factor.