ABSTRACT
The aim of this study was to examine the possible morphological and morphometric changes resulting from vitrification of embryos at the cleavage stage. In this study, 30 mice early-cleavage embryos at different stages of cleavage, resulting from in vitro fertilization [IVF] techniques, were examined before and after vitrification. Digital images were taken from embryos before and after vitrification. Zona pellucida thickness, differences in zona pellucida thickness, and diameter and volume of blastomeres and embryos as morphometric parameters and current rating of appearance of embryos as morphological parameters, have been studied. According to our findings, there were significant mean differences in all morphometric parameters of the two groups except in the zona pellucid thickness [P