14047例高龄孕妇无创产前检测的结果分析

Analysis of noninvasive prenatal testing in 14047 cases of advanced age pregnant women

目的探讨无创产前检测(non-invasive prenatal testing,NIPT)对于诊断高龄妊娠胎儿染色体非整倍体的价值。方法选择自愿接受NIPT检测的14047例高龄孕妇。回顾其NIPT以及羊水染色体核型分析的结果,追踪其妊娠结局。结果NIPT检测共提示21-、18-、13-三体异常104例、性染色体异常44例。经遗传咨询,在104例中87例接受了羊水染色体核型分析,确诊胎儿染色体异常63例,包括21-三体46例、18-三体11例、13-三体6例,阳性预测值(positive predictive value,PPV)分别为83.64%(46/55)、61.11%(11/18)、42.86%(6/14)、特异度分别为99.93%、99.95%、99.94%,灵敏度均为100%。在44例中34例接受了羊水染色体核型分析,确诊11例,PPV仅为32.35%。阴性病例随访未发现非整倍体异常,阴性预测值为100%。结论NIPT作为一种高龄孕妇的产前筛查手段,对21-三体的PPV最高,其次为18-三体,而对性染色体的PPV较低。NIPT对21-、18-、13-三体的漏诊率极低,能够显著减少高龄孕妇的侵入性产前诊断。

Objective To assess the value of non-invasive prenatal testing(NIPT)for the diagnosis of fetal chromosomal aneuploidies among women with advanced gestational age.Methods 14047 pregnant women have voluntarily accepted the NIPT test.The results of NIPT and amniocytic karyotyping analysis were compared,and the outcome of pregnancy was followed up.Results NIPT has identified 104 cases with a high risk for trisomies 21,18 and 13,and 44 cases with a high risk for sex chromosome abnormalities.After genetic consultation,87 of 104 cases have accepted amniocyte chromosomal karyotyping.63 cases of fetal chromosome abnormality were confirmed,including 46 cases of 21 trisomy,11 cases of 18 trisomy and 6 cases of 13 trisomy.The positive predictive value was 83.64%(46/55),61.11%(11/18),and 42.86%(6/14),the specificity was 99.93%,99.95%,99.94%,and the sensitivity was 100%.Among the 44 cases,34 received amniocytic chromosomal karyotyping analysis,11 cases were confirmed,the positive predictive value was only 32.35%.No aneuploidy was found in the low-risk cases.The negative predictive value was 100%.Conclusion As a prenatal screening method for women with advanced gestational age,NIPT has the highest positive predictive value for trisomy 21 and trisomy 18,but a lower positive predictive value for sex chromosome abnormalities.NIPT has a very low rate of missed diagnosis of trisomies 21,18 and 13,which can significantly reduce the number of women undergoing invasive prenatal diagnosis.