Foetal and Placental Growth in the Mouse After Pre-implantation Development in Vitro Under Oxygen Concentrations' of 5 and 20%

Abstract

Blastocysts which developed from two-cell mouse embryos in culture tubes containing an atmosphere with 20 % oxygen had approximately 20 % fewer blastomeres than blastocysts which developed under an oxygen concentration of 5 %. When these smaller blastocysts were transferred to the uteri of pseudopregnant foster mothers, the foetuses developing were as viable as those developing from blastocysts cultured under 5 % oxygen, indicating their ability to regulate for a lower blastomere number by at least day 17 of development.