Ⅱ、Ⅲ级胚胎活检后体外发育能力的研究

In vitro development ability of biopsied embryos classified as gradeⅡ and grade Ⅲ.

目的:探讨形态学评价质量较差的胚胎有无活检价值,活检后能否正常发育。方法: 160个IVF和ICSI周期剩余的Ⅱ级、Ⅲ级胚胎,来自同一例患者分级相同的胚胎配对,随机分为实验组和对照组。实验组采用喷酸透明带打孔法取出1个卵裂球,对照组继续培养,对比两组囊胚的形成率、孵化率、囊胚细胞总数,并观察不同形态学特征的胚胎活检后的发育情况。结果:活检组胚胎囊胚形成率,囊胚总细胞数与对照组相比没有差别,但囊胚第6天孵出率活检组明显高于对照组;Ⅲ级胚胎活检后囊胚形成率、第6天孵化率、囊胚总细胞数均明显低于Ⅱ级胚胎;活检前细胞数少于7个的胚胎,活检后发育能力显著降低。结论:活检不影响胚胎体外继续发育的能力;Ⅱ级胚胎活检后具有较好的发育潜力,Ⅲ级胚胎活检后囊胚形成率较低,即使形成囊胚,细胞数也较少,不能正常发育;第3天活检时具有7个或7个以上卵裂球的胚胎具有较好的继续发育能力。

Objective:To evaluate in vitro development ability of biopsied embryos classified as gradeⅡ and grade Ⅲ.Methods:160 embryos classified as gradeⅡ and grade Ⅲ were studied.Two embryos with similar morphology that come from the same patient were matched.One cell was removed from embryos of experimental group by chemical drilling method.The embryos in control group were cultured continually.The percentage of blastocyst formation,hatching rate of blastocyst,total cell number at the blastocyst stage were compared between two groups.Developing potential of biopsied embryos with different morphology was also recorded.Results:The percentage of blastocyst formation and total cell number of the blastocyst was similar between two groups,but biopsied group had a significantly higher hatching rate on day 6 than that of control group.Compared with the embryos classified as grade Ⅱ,the embryos classified as grade Ⅲ had significantly lower blastocyst rate,hatching rate and total cell number of blastocyst after biopsy.Embryos with less than 7 cells on day three had significantly lower blastocyst rate and total cell numbers of blastocyst than embryos with 8 or more than 8 cells after biopsy.Conclusion:Biopsy didn′t affect the development potential of embryos.Embryos classified as grade Ⅱ have good developmental potential after biopsy.Embryos classified as grade Ⅲ have lower developmental potential after biopsy,if it develops to blastocyst stage,the total cell numbers decrease greatly and can not develop continually.On day 3,embryos with less than 7 cells have a significantly lower development potential after biopsy.