Ultrastructural deformity of ovarian follicles induced by different cryopreservation protocols

Ultrastructural deformities were monitored after cryopreservation of F1 (B6CBAF1) mouse ovaries by either slow freezing or vitrification. Vacuole formation in the ooplasm, zona pellucida, and the cytoplasm of follicular cells, and mitochondrial deformity were detected. These types of cryodamage demonstrated protocol specificity.