EFFECT OF OXYGEN CONCENTRATION ON DEVELOPMENT AND QUALITY OF EMBRYOS DURING INTRACYTOPLASMIC SPERM INJECTION (ICSI).

Background: Elevated and non-physiological O2 concentrations could create unfavorable conditions in the substrate to produce free oxygen radicals that cause oxidative stress, which may be involved in the etiology of defective embryo development with higher rates of fragmentation. Aim of the Work: to evaluate the effects of oxygen tension on the early development and quality of embryos during Intracytoplasmic sperm injection (ICSI) treatment cycles. Patients and Methods: This prospective cohort observational study was carried out in the Embryology Laboratory of Assisted Reproduction Unit at Ain Shams University Maternity Hospital in the period from Octoberof2014 to October of 2017.This study comprised 1143 female gametes (oocytes) from 100 ICSI cycles patients. All the oocytes were injected by the same embryologist and were divided after injection equally into two groups according to system of incubation. Results: Fertilization and division Rates were significantly lower among CO2 incubator group than among Triplet incubator group, No significant difference between Implantation Rate of cases underwent incubation at atmospheric versus low oxygen tension and versus mix of both, No significant difference between outcomes in cases underwent incubation at atmospheric versus low oxygen tension and versus mix of both. Conclusion: Our findings support the idea that human embryo culture in low oxygen tension will improve the fertilization and embryo development, and ART outcomes