Culture of human embryos in alpha modification of Eagle's medium under low oxygen tension and low illumination.

Objective To determine whether protection from oxidative stress would enhance the development of human embryos. Design A new culture system for human IVF-ET that used low oxygen tension (5% O 2 ) and low illumination (20 lux from the ceiling and 100 lux from the microscope) throughout embryo manipulation was developed. The culture medium was similarly altered to contain neither transition metals nor hypoxanthine ( α MEM). Setting In vitro fertilization-embryo transfer program at Kyoto University Hospital. Patients One hundred ten IVF cycles performed using the new culture system between January 1991 and March 1992. Main Outcome Measures An analytical review of 110 IVF cycles that were performed using the new culture system was undertaken. Results The blastulation rate of spare (deselected) embryos was 58.5% (182/311). The pregnancy and live birth rates were 28.2% and 17.2%, respectively. Conclusions This new culture system provides a relatively high blastulation rate in human IVF. These results suggest that protection from oxidative stress enhances the in vitro development of human embryos.