扬州市9191例孕中期唐氏筛查结果分析

Analysis on screening results of Down's syndrome in 9191 cases during the second trimester of pregnancy in Yangzhou

目的探讨孕中期唐氏筛查对检出胎儿染色体异常及减少出生缺陷的实际意义。方法对扬州市9 191例孕15-20＋6周的孕妇用化学发光法对血清标志物甲胎蛋白（AFP）、人绒毛膜促性腺激素（β-HCG）和游离雌三醇（μE3）进行检测,结合孕妇年龄、体重、孕周等因素利用唐氏筛查风险评估软件计算胎儿患有21三体综合征、18三体综合征和神经管缺陷（NTD）的风险率,并对高风险孕妇进行羊水细胞染色体核型分析或B超进一步确诊。结果 9191例孕妇共筛查出611例高风险孕妇,阳性率为6.66%。347例高风险孕妇进行了羊膜腔穿刺术,经染色体核型分析共确诊10例染色体异常,其中21三体7例,18三体1例,其他染色体异常2例;143例NTD高风险孕妇经四维B超检查,最终确诊2例（脊柱裂1例、无脑儿1例）。结论中孕期唐氏筛查结合B超和羊水细胞染色体核型分析,可以有效降低出生缺陷患儿的出生率。

Objective To explore the practical value of Down＇s syndrome screening during the second trimester of pregnancy for detection of fetal chromosomal abnormalities and reducing birth defects. Methods Chemiluminescence was used to detect the concentrations of serum biochemical markers- alpha- fetoprotein（ AFP）,β- human chorionic gonadotropin（ β- h CG）,and unconjugated estriol in 9 191 pregnant women of 15- 20＋ 6gestational weeks in Yangzhou,Down＇s syndrome assessment software combined with maternal age,maternal weight and gestational weeks was used to calculate the risk degrees of fetal trisomy 21,trisomy 18,and neural tube defects（ NTDs）; for the high risk pregnant women,chromosomal karyotyping of amniotic fluid cells or type- B ultrasound was conducted for further definite diagnosis. Results Among 9 191 pregnant women,611 pregnant women were high risk pregnant women,the positive rate was 6. 66%. A total of347 high risk pregnant women underwent amniocentesis,after chromosomal karyotyping,10 pregnant women were diagnosed as chromosomal abnormalities definitely,including 7 cases of trisomy 21,1 case of trisomy 18,and 2 cases of other chromosomal abnormalities; 143 high risk NTDs pregnant women received four- dimensional ultrasonography,finally,2 cases were diagnosed definitely,including one case of spina bifida and one case of anencephaly. Conclusion Down＇s syndrome screening during the second trimester of pregnancy combined with ultrasonography and chromosomal karyotyping of amniotic fluid cells can effectively reduce the birth rate of infants with birth defects.