Patients recruited in this study will undergo IVF+/-ICSI treatment. They will undergo an ultrasound scan on the second or third day (day 2 or 3) of a period to exclude the presence of ovarian cyst and have the antral follicle count determined, which includes all follicles of 2-10 mm measured with a 5.5-7.5mHz transvaginal ultrasound probe. Blood will be checked for anti-mullerian hormone (AMH) measured by Beckman-Coulter Diagnostics.