目的 研究2014年1至12月复旦大学附属妇产科医院中孕期唐氏综合征血清学筛查（唐氏筛查）的阳性率和检出率,分析中孕期唐氏筛查的临床价值。方法 收集2014年1至12月复旦大学附属妇产科医院中孕期唐氏筛查对象19 718例,以双顶径核准的孕周为准,孕周为14~21周。收集血清三联检测[甲胎蛋白（alpha-fetoprotein,AFP）、β人绒毛膜促性腺激素（β-human chorionic gonadotrophin,β-hCG）和未结合雌三醇（unconjugated estriol,uE₃）]结果,计算各指标的中位数倍数(multiples of the median,MoM)值,结合孕妇年龄、体重、孕周等计算胎儿发生21-三体（唐氏综合征）、开放性脊柱裂(open spine bifida,OSB)、18-三体的风险值,并对妊娠结局进行随访。结果 2014年进行唐氏筛查的中孕期孕妇共19 718例,其中高风险孕妇1 264例,筛查总阳性率为6.41%。其中,35岁以下(不包括35岁)孕妇有18 660例,高风险者为1 015例,筛查阳性率为5.44%;35岁以上（包括35岁）孕妇为1 058例,高风险者为249例,筛查阳性率为23.53%。随访结果显示,有11例患儿确诊为唐氏综合征,其中9例筛查试验为阳性,2例筛查结果为阴性,21-三体检出率为82%（9/11）。随访结果还确诊了2例18-三体患儿和6例其他畸形患儿。结论 中孕期唐氏筛查无论是从检出率、经济价值,还是实验室可操作性考虑,依然是目前普及的产前筛查21-三体的首要和重要手段,同时还能筛查出18-三体、OSB及一些其他类型的畸形。

Objective: To investigate the value of second trimester prenatal serological screening for Down's syndrome by analyzing the positive rate of serological screening and the detection rate of Down's syndrome. Methods: From January to December 2014, prenatal serological screening for Down's syndrome was performed in 19 718 pregnant women in 14-21 weeks of pregnancy. Combined detection of alpha fetoprotein (AFP), β-human chorionic gonadotropin (β-hCG) and unconjugated estriol(uE₃) was performed on Beckman Access 2 Automatic Chemiluminescence Analyzer. Calculated the multiples of median (MoM) of above three indices and in coordinating with maternal age, body weight and weeks of pregnancy to predict the risk of 21-trisomy, open spine bifida (OSB), 18-Trisomy, and the pregnancy outcome was followed. Results: In the 19 718 pregnant women, serological triple screening revealed that 1 264 pregnant women were in high risk and had a positive screening rate of 6.41%. Among 18 660 pregnant women under 35 years old, 1 015 were in high risk and had a positive screening rate of 5.44%;; while for 1 058 pregnant women over 35 years old, 249 cases were in high risk and had a positive screening rate of 23.53%. Follow-up study showed that 11 pregnant women had baby with Down's syndrome, including 9 with screening positive and 2 with screening negative. The detection rate of 21-Trisomy was 82%. Follow-up also confirmed 2 cases of 18-Trisomy and 6 cases of other deformities. Conclusions: In considering the detection rate, economic aspect and operability of laboratory, serological screening in second trimester is still an important approach for screening Down′s syndrome, besides, 18-Trisomy, OSB and some other deformities can also been screened.