1134例不同指征的胎儿羊水染色体核型产前诊断分析

Prenatal diagnosis of chromosome karyotype of fetal amniotic fluid in 1 134 fetuses with different indications

目的:探讨具有不同产前诊断指征孕妇的染色体异常符合率,并评价母体外周血胎儿游离DNA无创产前基因检测(NIPT)作为产前一线筛查技术的临床应用价值。方法:选取2017年1月至2019年3月有产前诊断指征的1 134例孕妇为研究对象,在超声引导下行羊膜腔穿刺术,进行羊水细胞染色体核型分析。结果:共检出异常染色体核型91例,异常检出率为8.02%(91/1134)。其中染色体数目异常(包括嵌合体)79例(21-三体46例、18-三体13例、13-三体4例、性染色体异常6例、嵌合体10例),占86.81%(79/91);染色体结构异常12例占13.19%(12/91)。不同产前诊断指征羊水核型异常结果符合率:NIPT阳性率为88.24%(45/51)最高(P<0.01),其次为超声筛查异常率为9.73%(P<0.01),血清学筛查高风险率为3.81%(28/735),高龄发生率为3.42%(5/146),超声筛查异常发生率为9.73%(11/113),不良孕产史发生率为2.13%(1/47),其他2.38%(1/42)等产前指征之间的符合率差异均无统计学意义(P>0.05)。结论:产前血清学筛查(唐氏筛查)高风险是羊水穿刺的主要指征,孕中期NIPT可以为孕妇提供更加精准的筛查及优生指导。

Objective:To investigate the coincidence rate of chromosomal abnormalities in pregnant women with different prenatal diagnosis indications,and evaluate the clinical application value of noninvasive prenatal testing(NIPT) of maternal peripheral blood fetal free DNA as a first-line prenatal screening technology.Methods:The chromosome karyotype of amniotic fluid cells from ultrasound-guided amniocentesis in 1 134 pregnant women with different prenatal diagnosis indications from January 2017 to March 2019 were analyzed.Results:A total of 91 cases with abnormal karyotypes were detected,and the abnormal detection rate was 8.02%(91/1134).The abnormal chromosome number(including chimera) in 79 cases(86.81%) was found,which included 21 trisomy in 46 cases,18 trisomy in 13 cases,13 trisomy in 4 cases,sexual chromosome abnormality in 6 cases and chimera in 10 cases.The abnormal chromosome structure in 12 cases was identified,and the abnormal detection rate of which was 13.19%(12/91).The coincidence rate of the abnormal amniotic fluid karyotype with different prenatal diagnosis indications included that the positive NIPT of which was 88.24%(the highest)(P<0.01),the abnormal ultrasound screening of which was 9.73%(the second)(P<0.01).The differences of the coincidence rates of abnormal amniotic fluid karyotype among the serological screening with high risk(3.81%),high age(3.42),abnormal ultrasound screening(9.73%) and other(2.38%) were not statistically significant(P>0.05).Conclusions:The high risk of prenatal serological screening(Down′s screening) is the main indication of amniocentesis,which is the highest coincidence rate.The NIPT test in the second trimester can provide more accurate screening and eugenics guidance for pregnant women.