Better Quality and More Usable Embryos Obtained on Day 3 Cultured in 5% Than 20% Oxygen: A Controlled and Randomized Study Using the Sibling Oocytes.
To evaluate the effect of atmospheric oxygen (O2) concentration on embryonic development, a controlled and randomized study using the sibling oocytes was carried out. A total of 147 patients were studied. Embryos were cultured in O2 concentration 20% versus 5% during the gamete, zygote, and first 3 days. The mean cell numbers of embryo (7.69 ± 1.91 vs 7.20 ± 1.82, P = .011) and rate of clinically useable embryos (81.62% vs 77.22%, P = .017) were significantly higher in 5% O2 than in 20% O2. There was no difference in the zygote developmental stage, day 2, day 4, and blastocyst stage. The quality of blastocyst (both inner cell mass and trophectoderm) showed no difference. Also, there was no increase in embryos fragmentation and uneven cells in 20% O2 culture condition. In conclusion, 20% O2 reduced the mean cell numbers of embryo and the number of clinically useable embryos on day 3. However, there was no subsequent negative impact on development of day 4 and blastocyst stage.
Department of Obstetrics and Gynecology, The Second Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an, China.
Huixia
H
Peng
Assisted Reproduction Center, Maternal & Child Health Care Hospital of Shaanxi Province, Xi'an, China.
Wenhao
W
Shi
Respiratory Internal Medicine, Shaanxi Provincial People's Hospital, Xi'an, China.
Wei
W
Zhang
Assisted Reproduction Center, Maternal & Child Health Care Hospital of Shaanxi Province, Xi'an, China.
Xia
X
Xue
Assisted Reproduction Center, Maternal & Child Health Care Hospital of Shaanxi Province, Xi'an, China.
Na
N
Li
Assisted Reproduction Center, Maternal & Child Health Care Hospital of Shaanxi Province, Xi'an, China.
Wei
W
Li
Assisted Reproduction Center, Maternal & Child Health Care Hospital of Shaanxi Province, Xi'an, China shijuanzi123@126.com.
Juanzi
J
Shi
D004305:Dose-Response Relationship, Drug; D046149:Embryo Culture Techniques / Q000379:methods*; D004624:Embryo Transfer / Q000379:methods; D047108:Embryonic Development / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D054315:Oocyte Retrieval / Q000379:methods; D009865:Oocytes / Q000187:drug effects* / Q000502:physiology* / Q000637:transplantation; D010100:Oxygen / Q000008:administration & dosage*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies
D010100:Oxygen
culture condition; embryonic development; low oxygen culture; oxygen concentration