Embryo crypreservation is an established technique in our IVF program. While the stage at which embryos are frozen may differ from (zygotes, cleaved embryos, blastocysts), the process of saving spare embryos from a stimulated cycle has become routine for several reasons. First, the use of frozen embryos alleviates the need for the patient to go through another cycle of ovarian stimulation. Second, the replacement of fresh embryos in a stimulated cycle may be contraindicated because of patient illness or an elevated estradiol level, which may predispose the patient to hyperstimulation. Third, it is often more cost-efficient to pursue banked embryos that have already been created than to initiate another entire cycle of medications and oocyte retrieval. Embryo cryopreservation maximizes the stimulation and retrieval process without the transfer of too many fresh embryos, thereby lowering the risk of a multifetal gestation. GENESIS will freeze extra cleaved embryos or blastocysts created during a fresh cycle, that are of good quality. If the fresh cycle fails, the frozen embryos can be thawed at a later date in hope of establishing a pregnancy.