[Vitrification of human cleaved embryos in vitro fertilization-embryo transfer]

To assess the outcome of thawing human cleaved embryos from cryopreservation by vitrification.

A total of 957 day 2 or day 3 embryos from 219 patients were thawed after vitrification with ethylene glycol 5.5 solution and 0.25 ml straw between Jan 2003 and Jun 2005, 514 embryos were recovered and transferred in 178 patients.

The survival rate of thawing embryos and the clinical pregnancy rate after transfer was 72.2% and 19.7% respectively. Twenty-two healthy babies were born from 16 deliveries, including 12 girls and 10 boys, 6 pregnancies ended in miscarriage and another 13 are ongoing.

Vitrification method is an alternative for cryopreservation of human cleaved embryos because of high effectiveness, convenience and good cost efficiency.