2019年北京市孕妇外周血胎儿游离DNA检测现状分析

Status of detecting fetal free DNA in maternal peripheral blood in Beijing in 2019

目的了解2019年北京市孕妇外周血胎儿游离DNA筛查、产前诊断及妊娠结局的情况。方法采用描述性统计学方法分析2019年北京市8家产前诊断机构孕妇外周血胎儿游离DNA筛查及诊断情况。结果2019年北京市8家产前诊断机构共进行外周血胎儿游离DNA检测65136例,占产妇总数的29.8%(65136/218396)。21\18\13-三体综合征检测复合阳性预测值为57.4%(152/265),21-三体检测阳性预测值为76.0%(117/154),18-三体检测阳性预测值为38.9%(28/72),13-三体检测阳性预测值为18.0%(7/39),性染色体检测阳性预测值为30.5%(85/279),其他染色体检测阳性预测值为16.4%(30/183)。65136例患者中,适用人群筛查10791例,占16.6%;慎用人群筛查53833例,占82.7%;不适用人群筛查343例,占0.5%。追访发现1例21-三体和1例18-三体假阴性患者。21\18\13-三体综合征检出率为98.7%(152/154),其中21-三体检出率为99.2%(117/118),18-三体检出率为96.6%(28/29),13-三体检出率为100%(7/7)。非侵入性产前检查(NIPT)高风险孕妇产前诊断率为84.6%(615/727),其中21\18\13-三体综合征的产前诊断率为91.7%(243/265)。结论孕妇外周血胎儿游离DNA检测已成为21-三体综合征筛查的重要手段之一,在临床应用中应严格掌握检测指征,重视检测前后的遗传咨询,提高产前诊断率,同时加强实验室质控,提高检测质量。

Objective To assess the prenatal screening,diagnosis and pregnancy outcomes status with noninvasive prenatal testing(NIPT)in Beijing in 2019.Methods Descriptive statistical methods were used to analyze the screening and diagnosis status by detecting fetal free DNA in maternal peripheral blood in 8 prenatal diagnosis institutions in Beijing.Results A total of 65136 cases of pregnant women accepted NIPT in the 8 institutions in 2019,accounting for 29.8%of the total number of pregnant women(65136/218396).The compound coincidence positive predictive rate of 21\18\13-trisomy syndrome was 57.4%(152/265),the coincidence rates of 21-trisomy,18-trisomy,13-trisomy,sex chromosomes and other chromosomes were 76.0%(117/154),38.89%(28/72),18.0%(7/39),30.5%(85/279)and 16.4%(30/183),respectively.Among the 65136 pregnant women,10791 cases were suitable for population screening(16.6%);53833 cases were used with caution(82.7%);343 cases were not suitable for population screening(0.5%).By following-up,one case of 21-trisomy and one case of 18-trisomy were found to be false negative cases.The detection rate of 21\18\13-trisomy syndrome was 98.7%(152/154),of 21-trisomy was 99.2%(117/118),of 18-trisomy was 96.6%(28/29),and of 13-trisomy was 100%(7/7).The prenatal diagnosis rate of NIPT was 84.6%for high-risk pregnant women(615/727),of them the prenatal diagnosis rate was 91.7%(243/265)for 21\18\13-trisomy syndrome cases.Conclusions Detection of fetal free DNA in maternal peripheral blood(NIPT)has become one of the important methods of screening 21-trisomy syndrome.In clinical applications,doctors should strictly grasp the test indications,pay attention to genetic counseling before and after testing,improve the prenatal diagnosis rate,strengthen laboratory quality control and improve the quality of testing.