The developmental ability of vitrified-warmed embryos after cold storage. The
embryos stored in the refrigerator for 0, 24, 48, 72, or 96 h (A: 0 h, B: 24 h, C:
48 h, D: 72 h, E: 96 h) and then vitrified. The developmental rate was calculated as
follows: (Number of four-cell embryos, morulae, or blastocysts/Number of two-cell
embryos) × 100. Results are expressed as the mean ± SD (n=4–15).
*P<0.05 compared with Cold-stored embryos. More than 27 embryos
were analyzed in each experiment, and the total number of analyzed embryos in each
experimental group was as follows (0 h-Cold: 457, 0 h-Vitrified-Cold: 328,
0h-Cold-Vitrified: 197, 24 h-Cold: 397, 24 h-Vitrified-Cold: 236, 24 h:
Cold-Vitrified: 166, 48 h-Cold: 426, 48 h-Vitrified-Cold: 324, 48 h-Cold-Vitrified:
167, 72 h-Cold: 397, 72 h-Vitrified-Cold: 257, 72 h-Cold-Vitrified: 205, 96 h-Cold:
456, 96 h-Vitrified-Cold: 227, and 96 h-Cold-Vitrified: 208).