Received April 30, 1998
Accepted October 17, 1998

Introduction: A prospective and randomized study ofovarian stimulation with human recombinant FSH (rFSH;Gonal-F) versus highly purified urinary FSH (uFSH-HP; Metrodin-HP) was conducted on patients submitted to an ICSI program. similar(p=0.46) to the number obtained from patients who used u-FSH-HP(group II=5.5±3 .7), as also was the number of transferred embryos(group I=2.8±0.8;group II=2.6±0.9; P=0.27). Implantation rate (26.1%) and clinical pregnancy rates per puncture (36.7%) and per embryo transfer (37 .9%) were higher in patients who used r-FSH than in patients who used u-FSH-HP(19.5%, 31.7%, and 32.2%, respectively), but the differences were not statistically significant. The abortion rate(p=0.32) did not differ between groups(group I=4.5% versus group II=15.7%). Conclusion: Thus far, the data do not demonstrate significant differences in ovary stimulation with r-FSH versus u-FSH in patients whose indication for assisted reproduction was the male factor.