To evaluate whether there were significant differences in the effects of constant (5%) versus sequential (5%-2%) oxygen concentration protocols in embryo culture on term live birth rates.
This study will be conducted in five centers including the Clinical Center of Reproductive Medicine, First Affiliated Hospital of Nanjing Medical Universit. 980 women who wish to undergo blastocyst transplantation will be included in the study.
The study data will be analyzed statistically.
Female: age ≥20 and ≤40 years, male: age ≥20 and ≤50 years;
Proposed 1st or 2nd cycle of IVF or ICSI fertilization;
≥ 4 transferable embryos at oocyte stage.
Diagnosis of abnormal uterine cavity morphology (confirmed by 3D ultrasound or hysteroscopy), including uterine malformations (mediastinal uterus, unicornuate uterus, bicornuate uterus), submucosal uterine fibroids, or uterine adhesions;
Patients who are proposed to undergo IVM;
Patients who are proposed to undergo PGD/ PGS;
Patients with untreated severe hydrosalpinx (confirmed by ultrasound or HSG);