Department of Obstetrics, Gynaecology, and Neonatology, Infertility Unit, Fondazione Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan, Italy.
Reprod Sci. 2008 Dec;15(10):1027-33. doi: 10.1177/1933719108322437.
The aim of the this study was to compare the in vitro developmental competence of parthenogenetically activated oocytes cryopreserved with slow-freezing or vitrification. Supernumerary metaphase II oocytes obtained during in vitro fertilization procedures were randomized to slow freezing or vitrification procedure. After thawing or devitrification, oocytes were parthenogenetically activated and cultured. Survival, activation, development rate, and cell number during culture were compared. The 2 groups showed no significant differences between the rates of parthenogenetic activation, development, good quality parthenotes and blastomere number on day 2 of culture. However, parthenotes from the devitrified oocytes continued cleaving till day 3 in a significantly low proportion (27% vs. 42%). On day 3, the mean number of blastomeres was also lower in vitrification group compared to slow-freezing (4.8 + 1.9 vs. 5.8 + 1.7). In conclusion, parthenogenesis highlights a reduced potential of vitrified oocytes to cleave on day 3 compared with oocytes from slow-freezing.
本研究旨在比较玻璃化冷冻和慢速冷冻保存的孤雌激活卵的体外发育能力。体外受精过程中获得的多余的中期 II 期卵随机分为慢速冷冻或玻璃化冷冻程序。解冻或去玻璃化后，卵进行孤雌激活和培养。比较了存活、激活、发育率和培养过程中的细胞数量。两组之间孤雌激活率、发育率、优质孤雌原核和第 2 天培养的胚胎细胞数均无显著差异。然而，来自去玻璃化卵的原核在第 3 天继续分裂的比例明显较低（27%对 42%）。第 3 天，与慢速冷冻相比，玻璃化组的胚胎细胞数也较低（4.8 + 1.9 对 5.8 + 1.7）。总之，与慢速冷冻相比，玻璃化冷冻的卵在第 3 天的分裂潜能降低。
