Ultra-low oxygen tension during in vitro fertilization improves embryonic and adult outcomes [RNA-seq]

Importantly, O2 influences gene expression, metabolism, and the activity of important epigenetic enzymes. In clinics today, the lowest O2 tension used during embryo culture is 5%, despite evidence that portions of the mammalian female reproductive tract have O2 levels as low at 2%.

This suggests lower O2 may better mimic the in vivo environment, and thus lead to improved pre- and postnatal outcomes in IVF-conceived offspring. Using our validated IVF mouse model, we show embryo culture at 2% O2 compared to culture under 5% O2 significantly improves cell numbers and the chromatin landscape in preimplantation embryos, fetal and placental development during gestation, and metabolic functions in adulthood.