 This multicenter, randomized, open-label study will be performed in approximately 990 healthy females undergoing IVF. Each study center will follow their study center standard practice for IVF unless otherwise noted in this protocol. The study centers will be provided with the medications for down regulation, stimulation and ovulation induction. The subjects will be randomized to study medication on the day of oocyte retrieval or the day following and will continue treatment for up to 10 weeks. The subjects with a confirmed pregnancy will be required to return to the clinic several times during the course of the 10 week treatment period for serum pregnancy tests and transvaginal ultrasounds to monitor the pregnancy. 