984例高龄孕妇无创产前基因检测结果与妊娠结局分析

Analysis of NIPT test results and pregnancy outcomes of 984 advanced pregnant women

目的:探讨无创产前基因检测技术(NIPT)对高龄孕妇行产前胎儿染色体异常筛查结果。方法:对2018年9月-2020年1月来本院自愿要求行NIPT检测的高龄孕妇984例进行回顾性分析。对NIPT检测提示染色体异常者行羊膜腔穿刺,并行染色体核型分析或基因芯片检测。电话随访妊娠结局。结果:984例NIPT检测染色体异常14例(1.42%),其中21-三体4例、18-三体3例、13-三体2例、性染色体异常4例,其他染色体异常1例。对14例行产前诊断检出染色体异常10例,其中21-三体3例、18-三体2例、13-三体2例、性染色体异常3例、其他染色体异常0例;NIPT阳性预测值分别为75.0%、66.7%、100%、75.0%、0%。经随访,产前诊断明确染色体异常10例中有9例选择引产终止妊娠,其中3例21-三体高风险(47,XN,+21),2例18-三体高风险(47,XN,+18)、2例13-三体高风险(47,XN,+13),1例X高风险(45,X)及1例XXY高风险(47,XXY);1例XXX高风险(47,XXX)坚持正常妊娠,产后新生儿状况正常。其余4例产前诊断结果正常(46,XN),新生儿状况正常。结论:NIPT应用于高龄孕妇有较好筛查价值,但提示异常者仍需进行介入性产前诊断,从而避免假阳性或非必要引产。

Objective:To explore the value of non-invasive prenatal genetic testing(NIPT)for diagnosing prenatal fetal abnormal chromosome of advanced pregnant women.Methods:From September 2018 to January 2020,a retrospective analysis was made on 984 advanced pregnant women who volunteered to undergo NIPT test.Amniocentesis and chromosome karyotype analysis were performed in women with abnormal chromosome detected by NIPT.The pregnancy outcomes of these advanced pregnant women were followed up by telephone.Results:There were 14(1.42%)pregnant women with chromosomal abnormalities by NIPT,which included 4 cases with trisomy 21,3 cases with trisomy 18,2 cases with trisomy 13,3 cases with abnormal sex chromosome,and no other abnormal chromosomes.The positive predictive value of NIPT for screening fetal abnormal chromosome were 75.0%,66.7%,100%,75.0%,and 0%,respectively.After followed up,9 women in 10 women with fetal chromosome abnormality identified by antenatal diagnosis had experienced termination of pregnancy,which included 3 cases with fetal trisomy 21(47,XN,+21),2 cases with fetal trisomy 18(47,XN,+18),2 cases with fetal trisomy 13(47,XN,+13),1 case with fetal abnormal X chromosome(45,X),and 1 case with fetal abnormal Y chromosome(47,XXY).1 women with fetal abnormal X chromosome(47,XXX)continued to pregnancy,which’s newborn was normal.All 4 women with fetal normal chromosome(46,XN)by antenatal diagnosis had delivered normal newborns.Conclusion:NIPT has good screening value for advanced pregnant women,but it suggests that pregnant women with suspected fetal abnormal chromosome should be given interventional prenatal detection,so as to avoid false positive or unnecessary induced labor.