All patients will have gonadotropin antagonist protocol with Human menopausal gonadotrophin (hMG) stimulation until the day of hCG administration. On the day of hCG administration, ovarian ultrasound scan will be performed using a transvaginal probe. Oocytes will be aspirated 34-36 hours after HCG administration. Oocytes will be fertilized and embryos will be transferred. Both groups will be compared regarding the proportion of ongoing pregnancy.