The results of 42 zygote intra-Fallopian transfer cycles in 37 couples with persistent male infertility are reported. Of 396 retrieved oocytes, 39.1% fertilized normally and 63 zygotes were replaced in 25 cycles. Twelve patients became pregnant, including two twin pregnancies. The pregnancy rate was 28.6% per started cycle and 48.0% per replacement. The implantation rate per replaced zygote was 22.2% (14 of 63 replaced zygotes implanted). Sixty-two supernumerary zygotes or embryos were cryopreserved for later use.