植入前遗传学筛查中不同形态特征的胚胎整倍体率比较

Comparison of euploid rates among embryos with different morphological features in preimplantation genetic screening

目的通过植入前遗传学筛查患者的胚胎和染色体结果分析,比较不同发育形态参数胚胎的整倍体和非整倍体率。方法收集2015年1月1日至2017年4月30日西北妇女儿童医院生殖中心行植入前遗传学筛查(PGS)患者,胚胎培养至卵裂期和囊胚期活检,PGS检测采用array-CGH(BlueGnome 24SureV3),卵裂期评价主要参数为D3天胚胎卵裂球数目、碎片体积比例和不均卵裂球数目。囊胚评价采用Garnder囊胚分级法。比较胚胎的形态参数与整倍体的发生率。结果 PGS共活检348枚胚胎,成功检测322枚胚胎,其中整倍体胚胎数目为123(38.2%),非整倍体胚胎数目为199(61.80%)。卵裂期胚胎碎片体积比例在整倍体与非整倍体组中具有统计学差异(t=-2.60,P<0.05),D 3天胚胎卵裂球数目和不均卵裂球数目未检验出统计学差异。活检时囊胚扩张期别在整倍体与非整倍体发生率具有统计学差异(χ2=2.00,P<0.05),活检时间(D4~D5,D6)、内细胞团形态(A/B,C)和外胚层形态(A/B,C)无统计学差异(χ2值分别为0、0、1.69,均P<0.05)。结论通过PGS患者的染色体结果分析得出,卵裂期胚胎评价参数中胚胎的碎片体积比例低的胚胎整倍体率较高,囊胚形态参数中活检时的囊胚扩张期别较高的囊胚整倍体率较高。

Objective To compare the euploidy and aneuploidy rates of embryos with different morphological parameters by analyzing the chromosome results and embryos of patients in preimplantation genetic screening（PGS）.Methods The patients who underwent preimplantation genetic screening in the Center for Assisted Reproduction of Northwest Women and Children＇s Hospital during January 1,2015 to April 30,2017 were collected.Their embryos were cultured to biopsy in the cleavage and blastocyst stage.Array-CGH（BlueGnome 24 SureV3）was adopted for PGS.The main parameters for the evaluation of cleavage stage were the number of blastomeres on D3,the ratio of fraction volume and the number of non-uniform blastomeres.The blastocyst was evaluated by Garnder blastocyst grading.The morphological parameters of the embryos and the incidence of euploidy were compared.Results A total of 348 embryos were biopsied by PGS and 322 embryos were successfully detected.The number of euploid embryos was 123（38.2%）while the number of aneuploid embryos was 199（61.80%）.The difference in the ratio of fraction volume during cleavage stage between euploid group and aneuploid group was statistically significant（t=-2.60,P 0.05）.There were no statistically significant differences in the number of blastomeres and the number of non-uniform blastomeres on D3.There was statistically significant difference in the incidence of euploidy and aneuploidy in the expansion stage of blastocyst during biopsy（χ2=2.00,P0.05）.However,there were no statistically significant differences in biopsy time（D4-D5,D6）,morphology of inner cell mass（A/B,C）and ectoderm morphology（A/B,C）（χ2 value was 0,0 and 1.69,respectively,all P0.05）.Conclusion By analyzing the chromosome results of patients in preimplantation genetic screening,in the cleavage stage embryo evaluation parameters,the embryos with low ratio of fragments volumes are of higher incidence of euploidy,while in blastocyst morphological parameters,the embryos with higher expansion stage of blastocyst during biopsy are of higher incidence of euploidy.