目的 分析无创产前基因检测(NIPT)在胎儿染色体非整倍体疾病诊断中的检出效率及临床应用价值。方法 选取2016年4月—2018年3月在我院接受无创产前基因检测的3 759例孕妇作为研究对象,利用二代测序AR550平台结合生物信息学进行无创产前基因检测,NIPT 的检测范围包括21、18、13 及性染色体非整倍体。对 NIPT 高风险的孕妇,建议行羊水或脐血穿刺染色体核型分析,比较两者结果的一致性,并随访妊娠结局。结果 3759例孕妇中NIPT提示高风险27例,阳性率为0.71%。其中24例孕妇行染色体核型分析,确诊为 21-三体14例、18-三体1例、13-三体1例和性染色体数目异常4例,阳性预测值分别为100%、50%、100%和66.7%。其中NT增厚中无创孕妇99例,检出高风险为5例,检出率为5.05%（5/99）,明显高于总体检出率。结论 NIPT 对 21-三体和 18-三体具有较高的敏感性和特异性,能提高产前筛查和诊断效率,具有较好的临床应用价值.

Objective To analyze the efficiency and clinical value of noninvasive prenatal gene test (NIPT) in the diagnosis of fetal chromosomal aneuploidy. Methods From April 2016 to March 2018, 3 759 pregnant women who underwent noninvasive prenatal gene testing in our hospital were selected as subjects. The second generation sequencing AR550 platform combined with bioinformatics was used for noninvasive prenatal gene testing. The NIPT detection ranged from 21, 18, 13 to sex chromosome aneuploidy. For pregnant women at high risk of NIPT, amniotic fluid or umbilical cord blood puncture karyotype analysis was recommended to compare the consistency of the two results, and follow-up pregnancy outcomes. Results Among 3 759 pregnant women, NIPT showed 27 cases of high risk, with a positive rate of 0.71%. Twenty-four pregnant women were diagnosed as 21-trisomy in 14 cases, 18-trisomy in 1 case, 13-trisomy in 1 case and abnormal sex chromosome number in 4 cases. The positive predictive values were 100%, 50%, 100% and 66.7% respectively. Among them, 99 cases were non-invasive pregnant women with NT thickening, and 5 cases were at high risk of detection. The detection rate was 5.05% (5/99), which was higher than the overall detection rate. Conclusion NIPT has high sensitivity and specificity to 21-trisomy and 18-trisomy, can improve the efficiency of prenatal screening and diagnosis, and has good clinical application value.