玻璃化冷冻对胚胎体内外发育潜能的影响

目的观察新鲜8-细胞胚胎和玻璃化冷冻复苏8-细胞胚胎在囊胚形成率、囊胚孵出率及胚胎种植率、小鼠出生率的差异,探讨玻璃化冷冻对胚胎体内外发育潜能的影响。方法性成熟期雌鼠（〉6～7周龄）106只,取2-细胞胚胎,培养至6～8细胞胚胎时分为新鲜胚胎进行移植（新鲜移植组）和玻璃化冷冻（玻璃化冷冻组）,2周后复苏移植。2组各取50枚移植前胚胎,体外培养48～72h,观察2组胚胎体外培养发育至囊胚及囊胚孵出情况。新鲜胚胎及复苏后的8-细胞胚胎经1～3h培养,选择外形正常胚胎移植于假孕63～67h的受体母鼠的两侧子宫中,妊娠17～20d自然分娩后记录产仔数,比较2组妊娠率、小鼠出生率。结果新鲜移植组囊胚形成率、孵出率、妊娠率、出生率分别为92%,84%,48.93%,13.16%,玻璃化冷冻组囊胚形成率、孵出率、妊娠率、出生率分别为90%,86%,47.06%,12.62%,2组差异均无统计学意义（P〉0.05）。结论玻璃化冷冻复苏对小鼠胚胎体内外发育潜能无明显影响。

Embryos developmental capacity of vitrified 8-cell embryos in vitro or in vivo

Objective To observe the blastocyst formation rate,blastocyst hatching rate,embryo implantation rate,the birth rate of vitrified 8-cell embryos in mice compared with fresh 8-cell embryos and to evaluate the impact of vitrification on embryos developmental ability in vitro and in vivo.Methods A total of 106 females mice（6 to 7 weeks old） were used in this experiment.After 36 hours of culture,2-cell embryos were obtained and observed embryonic development.And 6-to 8-cell embryos were divided into fresh-embryo group（fresh embryo transfer）,and vitrified-embryo group（vitrified embryos were stored for 2 weeks in liquid nitrogen,then thawed and transfer）.Fifty pre-transferring embryos were cultured for 48 to 72 hours in vitro in each group.The numbers of blastocysts and hatched blastocysts were recorded.After 1 to 3 hours of culture from thawing,the morphologically normal 8-cell embryos were selected to transfer to each side of uterus in pseudopregnant mouse for 63 to 67 hours.Fresh transplantation group was transferred fresh 8-cell embryos.The number of live pups was recorded after 17 to 20 days of pregnancy by natural delivery.The pregnancy rate and birth rate were compared between two groups.Results The blastocyst formation rate,the blastocyst hatching rate,the pregnancy rate and the birth rate were 92%,84%,48.93% and 13.16% in fresh-embryo group and 90%,86%,47.06% and 12.62% in vitrified-embryo group,which showed no significant differences between two groups（P0.05）.Conclusion Vitrification has less impact on the mice embryos developmental capacity in vitro and in vivo.