[Effect of oxygen concentration on outcome of in-vitro fertilization-embryo transfer].

OBJECTIVE: To investigate the effect of low and high oxygen concentration on embryo development, pregnancy outcome and birth defects of in vitro fertilization-embryo transfer (IVF-ET).

METHODS: According to the oxygen concentration of in vitro culture environment, the IVF-ET performed in the Women's Hospital, Zhejiang University School of Medicine during 2013 and 2015 were divided into low oxygen concentration group ( n =2036, 5% O2 ) and high oxygen concentration group ( n =4617, 20% O2 ). The rate of fertilization, good quality embryo, clinical pregnancy, ectopic pregnancy, abortion and birth defect were compared between two groups.

RESULTS: The good quality embryo rate was significantly higher in the low oxygen concentration group ( P <0.05). However, no significant differences were found between two groups in the rate of fertilization, clinical pregnancy, ectopic pregnancy, abortion and birth defect (all P >0.05).

CONCLUSIONS: Low oxygen environment may improve the potential of embryonic development, but its impact on pregnancy outcome and birth defect is not significant.