Inclusion Criteria:  Clinical diagnosis for primary or secondary infertility Healthy females Clinical diagnosis for unexplained infertility Females between 20 and 45 years old. Males between 20 and 50 years old. At least 3 retrieved oocytes per follicular puncture with at least 1 oocyte at germinal vesicle (GV) or metaphase I (MI) stage  Exclusion Criteria:  Presence of low quality oocytes Females with endometrial or ovarian infertility factor