title: Two different concentrations of oxygen for culturing precompaction stage embryos on human embryo development competence: a prospective randomized sibling-oocyte study.
abstract: The study was to investigate the effects of oxygen concentration at different levels for culturing pre-compaction embryos on human embryo development competence. A total of 1254 oocytes from 92 patients treated with conventional in vitro fertilization (IVF) were harvested in this study. Oocytes were randomly assigned to the atmospheric (~20%) or low (~5%) oxygen concentration groups on the retrieval day (day 0). Groups were compared with respect to fertilization rates, embryo development, and reproductive outcome. We failed to detect a significant difference on fertilization rate between two groups. However, the low oxygen group yielded more optimal embryos on day 3 when compared with the atmospheric group (72.4% vs. 64.2%). The low oxygen group had a significantly higher blastocyst formation rate than the atmospheric oxygen group (64.5% vs. 52.9%). It is seemly that the optimal blastocyst and frozen blastocyst rates was higher in the low oxygen group, but the data did not reach a statistical significance. Although the use of low oxygen will not affect the clinical outcome in the fresh cleavage-transfer cycles, but it will result in more favorable clinical outcomes in the subsequent warming blastocyst-transfer cycles, with statistically significantly higher clinical pregnancy rate (CPR) and implantation rate (IR) compared with atmospheric oxygen. In conclusion, a low oxygen concentration may significantly improve the developmental potential of pre-compaction embryos, thus resulting in a positive effect on subsequent blastocyst cultivation and optimizing the treatment cycle.
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430030, People's Republic of China.
authors.forename: Na
authors.initials: N
authors.lastname: Guo
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430030, People's Republic of China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Li
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430030, People's Republic of China.
authors.forename: Jihui
authors.initials: J
authors.lastname: Ai
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430030, People's Republic of China.
authors.forename: Longjie
authors.initials: L
authors.lastname: Gu
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430030, People's Republic of China.
authors.forename: Wen
authors.initials: W
authors.lastname: Chen
authors.affiliation: Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430030, People's Republic of China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Liu
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000378:metabolism*; D015687:Cell Hypoxia; D002681:China; D046149:Embryo Culture Techniques; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D059471:In Vitro Oocyte Maturation Techniques; D009865:Oocytes / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010100:Oxygen
keywords: Oxygen concentration; atmospheric oxygen; embryo development; sibling oocytes