不同产前筛查方案对胎儿染色体异常检出效率的比较

目的探讨不同产前筛查方案对胎儿染色体异常的检出效率。方法应用时间分辨免疫荧光法对24986例孕妇进行母体血清学二联筛查,根据风险值及后续的检查方案不同将人群分为高风险直接进行羊水穿刺组(A1组)、高风险行无创产前检测(non-invasive prenatal testing,NIPT)组(A2组)、临界风险进行超声软指标筛查组(B1组)及临界风险进行NIPT组(B2组)。并对各组妊娠结局进行随访后比较分析各组筛查方案对胎儿常见染色体异常检出效率的影响。结果(1)A1组390例直接经羊水穿刺确诊唐氏综合征(Downs’syndrome,DS)1例,爱德华综合征(Edwards’syndrome,ES)2例,其他染色体异常14例;A2组1001例NIPT检出高风险24例,经羊水穿刺确诊DS 9例,ES 2例,其他染色体异常6例,A2组漏诊1例ES及1例6号染色体小片段缺失(arrhg19]6p12.2(21,816,542-22,431,031)×1)。血清学筛查高风险A1组、A2组筛查方案对胎儿染色体异常的检出率分别为100%、89%,差异有统计学意义。(2)B1组确诊DS 2例,其他染色体异常2例,漏诊DS 2例;B2组确诊DS 1例,ES 1例,其他染色体异常2例。B1、B2筛查方案对血清学筛查临界风险者胎儿染色体异常的检出率分别为60%、100%,差异有统计学意义。结论(1)当血清学筛查结果高风险时,选择NIPT可获得最优的卫生经济学评价及更高的工作效率;(2)当血清学筛查为临界风险时,首选NIPT,在经济落后地区,对不接受NIPT者推广孕18~20周时软指标筛查作为补充。

Comparison of the detection rate of fetal chromosomal abnormalities using different prenatal screening strategies

Objective To investigate the detection efficiency of common chromosomal abnormalities in fetuses by selecting different further prenatal screening programs based on the risk results of maternal serological screening in the second trimester.Methods application of time-resolved immunofluorescence technique in 24986 cases of pregnant 15~20⁺⁶weeks to maternal serologic screening of pregnant women duplex screening.According to the risk value and the different follow-up screening schemes,the population was divided into the group of direct amniocentesis for high-risk serological screening(group A1)、non-invasive prenatal testing(NIPT)group for high-risk serological screening(group A2)、the group of soft marker screening for middle risk(group B1)and the group of NIPT for middle risk(group B2).Compared and analyzed the follow-up of pregnancy outcomes in each group,so as to understand the impact of different screening programs on the detection efficiency of common fetal chromosomal abnormalities.Results(1)In group A1 of 390 cases,1 case of Downs’syndrome(DS),2 cases of Edward s’syndrome(ES)and 14 cases of other chromosome abnormalities were confirmed by direct amniocentesis.In group A2,24 cases with high risk of NIPT were detected,9 cases of DS were confirmed by amniocentesis,2 cases of ES,6 cases of other chromosome abnormalities,1 case of 18-trisomy syndrome and 1 case of small fragment deletion of chromosome 6 were missed in the low risk group of NIPT.The detection rates of fetal chromosomal abnormalities in the high-risk A1 and A2 groups were 100%and 89%,respectively,withχ²=6.74,P=0.01.The differences were statistically significant.(2)Group B12 cases with DS confirmed by amniocentesis,2 cases with other chromosomal abnormalities,and 2 cases with missed diagnosis of DS in negative soft indicators.In group B2,1 case of DS,1 case of ES and 2 cases of other chromosome abnormalities were confirmed by amniocentesis.The detection rates of fetal chromosomal abnormalities in the middle-risk B1 and B2 groups were 60%and 100%.Conclusion(1)The first choice of NIPT can get the best health economic evaluation and higher worker efficiency when serological screening results for high risk.(2)When serological screening results are middle risks,chose NIPT first,In economically backward areas,soft marker screening should be actively promoted as a supplement when NIPT is economically restricted.