Biphasic oxygen tension promotes the formation of transferable blastocysts in patients without euploid embryos in previous monophasic oxygen cycles

Abstract

Abstract This study evaluated whether the concentration of biphasic O2 (5–2%) promotes the formation of qualified blastocysts (QBs) and euploid blastocysts and increases the probability of cycles with transferable blastocysts. Total 90 patients (180 cycles) without euploid blastocysts in previous monophasic O2 (5%) cycles were enrolled for an additional cycle of biphasic O2 (5–2%). In the biphasic O2 (5–2%) tension group, the rate of QB (35.8%, 225/628) were significantly higher than those in the monophasic O2 (5%) group ( 23.5%, 137/582; p < 0.001). In addition, the number of euploid blastocysts (0.5 ± 0.8) and the percentage of cycles with transferable blastocysts were significantly higher in the biphasic O2 (5–2%) group (57.8%, 52/90) than in the monophasic O2 (5%) group (0 and 35.6%, 32/90, respectively; p = 0.003). Multivariable regression analysis also indicated that the QB rate and the probability of cycles with transferable blastocysts correlated with O2 tension (OR: 1.535, 95% CI: 1.325–1.777, and OR: 3.191, 95% CI: 1.638–5.679, respectively; p < 0.001). Biphasic O2 culture can be used as an alternative strategy to increase the number of euploid QBs and the probability of cycles with transferable blastocysts in patients with a poor prognosis.