After administration of GnRH antagonist from day 1 of stimulation for IVF, 12.1 cumulus oocyte complexes were retrieved (95% confidence interval [CI], 10.6-13.6), 1.9 embryos were transferred (95% CI, 1.7-2.0), and 2.4 embryos were cryopreserved (95% CI, 1.7-3.1). Stimulation for 8.8 days (95% CI, 8.4-9.2) with recombinant FSH resulted in an ongoing implantation rate of 26.5% (95% CI, 17.1-35.9) and an ongoing pregnancy rate of 39.7% per started cycle (95% CI, 30.1-50.8) and of 42.4% per ET (95% CI, 32.3-53.1).