目的探讨开展高龄产妇无创产前基因检测(NIPT)对胎儿染色体非整倍体畸形的筛查效率。方法由卫生行政部门安排专项经费,将2017年4月28日-12月30日,在社区卫生服务中心登记的符合纳入及排除标准的2000例孕妇纳入研究,提供免费NIPT。对检测结果高风险者,进一步进行羊水穿刺及胎儿染色体核型分析。采用Kappa检验分析NIPT与胎儿染色体核心分析结果的一致性,统计NIPT的灵敏度、特异度、阳性预测值和阴性预测值。结果 2000例孕妇血样中,共检出17例胎儿染色体异常高风险个案。经羊水穿刺产前诊断,其中10例被确诊为胎儿染色体异常(包括6例21-三体综合征、2例18-三体综合征和2例性染色体异常)。NIPT对21-三体综合征、18-三体综合征、性染色体异常的灵敏度及阴性预测值均为100. 00%,特异度分别为99. 95%、100. 00%、99. 90%;阳性预测值分别为85. 71%、100. 00%、50. 00%;对常染色体异常的灵敏度和阳性预测值为0。NIPT与胎儿染色体核型分析比较,对21-三体综合征、18-体综合征的检验一致性较好。结论 NIPT服务具有良好的筛查效率,对出生缺陷防控具有重要意义,值得推广实施。

Objective To explore the screening efficiency of noninvasive prenatal gene testing( NIPT) for fetal chromosomal aneuploidy among pregnant women of advanced age. Methods A total of 2000 pregnant women who met the inclusion and exclusion criteria registered at the community health service center from April 28,2017 to December 30,2017 were included in the study,and received free NIPT. For those with high risk,further amniocentesis and fetal chromosome karyotype analysis were further carried out.Kappa test was used to analyze the consistency of NIPT and chromosome core analysis results. The sensitivity,specificity,positive predictive value and negative predictive value of NIPT were obtained. Results A total of 17 cases of fetal chromosomal abnormalities were detected among the blood samples of 2000 pregnant women. Ten of them were diagnosed as fetal chromosomal abnormalities by prenatal diagnosis such as amniocentesis( including 6 cases of 21-trisomy syndrome,2 cases of 18-Trisomy syndrome and 2 cases of sex chromosome abnormalities). The sensitivity and negative predictive value of NIPT to 21-trisomy syndrome,18-trisomy syndrome and sex chromosome abnormalities were all 100. 00%. The specificity were 99. 95%,100. 00%,and 99. 90%,respectively and the positive predictive value were 85. 71%,100. 00% and 50. 00%,respectively. The sensitivity and positive predictive value of NIPT to autosomal abnormalities was 0. Compared with fetal chromosome karyotype analysis,NIPT has a good consistency in the examination of21-trisomy syndrome and 18-trisomy syndrome. Conclusion NIPT has good screening efficiency and is of great significance for the prevention and control of birth defects,so it is worth popularizing and implementing.