解凍胚胎於2, 5, 20 % O2培養環境囊胚期形成率類似( 58.7% vs  63.6 % vs 66.7 %)
5% O2培養環境下囊胚品質較優

J Assist Reprod Genet. 2016 Mar 23. [Epub ahead of print]

Comparison of 2, 5, and 20 % O2 on the development of post-thaw human embryos.

Yang Y1,2,3, Xu Y1,4, Ding C1,4, Khoudja RY1,4, Lin M1,4,5, Awonuga AO2, Dai J2, Puscheck EE2, Rappolee DA2,3, Zhou C6,7.

Author information

Abstract

PURPOSE:

The objective of this study is to investigate the effect of 2, 5, and 20 % O2 on post-thaw day 3 human embryo culture until blastocyst stage.

METHODS:

One hundred fifty-five day 3 human embryos were used. One hundred twenty out of 155 embryos were recovered after thawing. Surviving embryos were distributed into 2, 5, or 20 % O2 groups and cultured for 2.5 days. At the end of culture, blastocyst formation was assessed, and then, embryos were collected for RT-qPCR or immunofluorescence analysis.

RESULTS:

Using visible blastocoel to define blastocyst formation, 58.7 % (27/46) of surviving day 3 embryos formed blastocyst at 2 % O2, 63.6 % (28/44) at 5 % O2, and 66.7 % (20/30) at 20 % O2. The difference in blastocyst formation rates was not significant. Average blastocyst cell number was 119.44 ± 11.64 at 2 % O2, 142.55 ± 22.47 at 5 % O2, and 97.29 ± 14.87 at 20 % O2. Average apoptotic rate was 4.7 % ± 0.4 % for blastocyst formed at 2 % O2, 3.5 % ± 0.7 % at 5 % O2, and 5.8 % ± 1.1 % at 20 % O2. Apoptosis rate was significantly lower for blastocysts formed at 5 % O2(p < 0.05). Compared with gene expression levels at 5 % O2, which were arbitrarily set as "1," 20 % O2 is associated with significantly higher expression of BAX (2.14 ± 0.47), G6PD (2.92 ± 1.06), MnSOD (2.87 ± 0.88), and HSP70.1 (8.68 ± 4.19). For all genes tested, no significant differences were found between 2 and 5 % O2.

CONCLUSION:

The result suggests that development of cryopreserved human embryos from day 3 to blastocyst stage benefits from culture at 5 % O2.