In group I , when at least one follicle ≥ 14 mm in mean diameter was observed , 0.25 mg GnRH antagonist (ganirelix , Organon, netherlands) SC daily was started and continued until hCG injection . Urinary Human chorionic gonadotropin 10000 IU was administered intramuscular when at least two follicles reached a mean diameter of 18 mm in both groups . Also , endometrial thickness and serum E₂ level were measured on the day of hCG injection .Oocyte retrieval was performed 34-36 hours after hCG injection and conventional IVF or intracytoplasmic sperm injection (ICSI) was done as appropriately . All embryos were scored by the number , size , shape , symmetry and cytoplasmic appearance of blastomers , and the presence of anucleate cytoplasmic fragmentation .