5694例单胎中孕期唐氏征血清学筛查效果分析

The effectiveness analysis of the serum screening test for the Down's syndrome in the second trimester in 5694 cases of single birth

目的探讨孕中期唐氏征血清学筛查在检出胎儿21-三体综合征的临床应用价值,对本实验室中期唐氏征血清学筛查进行效果分析。方法采15-20+6孕妇静脉血进行唐氏中期三联筛查,高风险结果无创产前筛查或直接产前诊断,电话随访妊娠结局。结果唐氏征血清学筛查共检出21-三体高风险病例379例,羊水细胞染色体核型分析共确诊胎儿21-三体综合征7例,18-三体综合征3例,13-三体综合征1例,嵌合体1例,其他染色体结构异常3例。随访结果唐氏征筛查高风险病例中,B超胎儿畸形的发生率明显高于低风险人群。结论中孕期唐氏征血清学筛查在检出胎儿21-三体综合征和B超结构异常病例中具有临床应用价值,本实验室21-三体筛查假阳性率6.5%(371/5686),检出率62.5%(5/8)。

Objectives.：To investigate the clinical application value of the Down＇ s serum screening tests in the second trimester for the detection of the 21-trisomy syndrome in the fetus, and to analyze the effectiveness of the Down＇ s serological screening tests conducted by our laboratory. Methods. Venous blood were collected for pregnant women at 15-20^＋6 weeks of pregnancy for screening of Down＇ s interim triple, and those at high risk were further detected by the non-invasive prenatal screening tests or direct prenatal diagnosis. Pregnancy outcomes were followed up by telephone. Results. The serum screening for Down＇s detected 379 high-risk cases of 21-trisomy, while the karyotype analysis of amniotic fluid cells of fetuses diagnosed seven cases of 21-trisomy, three cases of 18-trisomy, one case of 13-trisomy syndrome, one case of chimeras, and 3 cases with other chromosomal structural abnormalities. Follow-up results demonstrated that while compared with those at low risk, the rate of fetal malformations by the B-type ultrasonic diagnosis was significantly higher for the high-risk cases detected by the Down＇ s screening test. Conclusion： Down trimester serum screening tests showed clinical value in the detection of fetuses with the 21-trisomy or the B-type ultrasonic malformations. The false-positive rate of the 21-trisomy screening test in the second trimester in our laboratory was 6.5% （371/5686） , with the detection rate of 62.5% （5/8） .