Comparison of the effects of 5% and 6% co2 culture systems for human IVF embryos from woman older than 40 years of age: a prospective randomized study

Abstract

The negative correlation between fecundity and age in women has been extensively documented. Many efforts have been tried to increase the pregnancy rate in old aged woman(≥40 years of age) undergoing an IVF treatment cycles. While recent development of optimized culture media for culturing human embryos in vitro has provided reliable clinical results, the fertility of aged women remain relatively low. When using bicarbonate-buffered media, the concentration of CO2 influences directly on pH of media and embryo quality.