All participants will be undergoing an IVF/ICSI cycle utilizing either long gonadotropin releasing hormone (GnRH) agonist or GnRH antagonist protocols. In the long GnRH agonist cycles, participants will take a combined oral contraceptive pill (OCP) for 21-42 days. The GnRH agonist buserelin acetate (0.2 mg subcutaneously daily) will be started 5 days before the last OCP is taken, for a 5-day overlap, and continued until the day of hCG trigger. In the GnRH antagonist cycles, women will either be down-regulated with an oral combined contraceptive pill (OCP) for 14-21 days, starting on cycle day 3 of the pre-stimulation cycle, or with estrogen 4 mg orally daily starting approximately 7 days post-ovulation in the pre-stimulation cycle. Participants continue the OCP or estrogen until the designated stop day as determined by the clinic schedule. In both agonist and antagonist cycles, FSH will be given to each patient in either recombinant or human menopausal gonadotropin (HMG) forms, at doses ranging from 150 IU (international units) to 300 IU daily, as per investigator judgment. FSH will start on either a natural day 3 following OCP or estrogen withdrawal, or on an 'assigned' day 3, based on scheduling requirements. The FSH dose will be maintained for 4 days, after which dose titration can occur according to results of follicular development seen on transvaginal ultrasonography and serum estradiol levels, which first occurs on cycle day 7. Continued ultrasonographic and serum level monitoring will occur every 1-2 days until time of human chorionic gonadotropin (hCG) trigger. In the GnRH antagonist cycles, a GnRH agonist will be started at a dose of 250 mcg daily when any of the following first occurs: cycle day 9, estradiol level > 2000 pmol/L, lead follicle > 14 mm in diameter, and will be continued until time of hCG trigger. Timing of hCG (5000-10,000 IU) administration will occur once at least three lead follicles have diameters > 17 mm. Oocyte retrieval will be performed 36 hours after hCG administration.