血清学联合系统超声在孕中期唐氏综合征、三体综合征及神经管畸形胎儿筛查中的应用研究

目的 探讨血清学联合系统超声在孕中期唐氏综合征、三体综合征及神经管畸形胎儿筛查中的应用价值。方法 选取2017年12月至2020年12月孕中期在金华市妇幼保健院接受产前血清学及系统超声检查的单胎孕妇5236例作为研究对象。血清学检测指标包括游离人绒毛膜促性腺激素（free human chorionic gonadotropin，fHCG）、甲胎蛋白（alpha fetoprotein，AFP）、游离雌三醇（unconjugated estriol，uE3），使用软件进行风险值计算，对高风险孕妇行羊膜腔穿刺羊水细胞培养核型分析，对比血清学、超声单项筛查与联合筛查的诊断效能。结果 5236例孕妇经产前诊断出56例先天性缺陷胎儿，发生率1.07%。血清学单项检出阳性288例，阳性率5.50%；超声单项检出阳性116例，阳性率2.22%；血清学联合系统超声检出阳性82例，阳性率1.57%。血清学、超声、血清学联合系统超声筛查的阳性率及真阳性率比较，差异均有统计学意义（P<0.05），血清学联合系统超声筛查的阳性率最低，但真阳性率最高。血清学联合系统超声筛查的敏感度、特异性、阳性预测值均显著高于血清学与超声单项筛查，假阳性率、假阴性率则显著低于血清学与超声单项筛查（P<0.05）。血清学联合系统超声筛查结果为高风险者的妊娠结局异常率达10.98%，显著高于低风险者的妊娠结局异常率（1.36%，P<0.05）。结论 相比单一血清学及超声筛查，孕中期采用血清学联合系统超声筛查对胎儿神经管畸形、三体综合征、唐氏综合征的筛查准确率更高，二者联用能筛查出大部分胎儿结构畸形，减少出生缺陷。

Application of serology combined with systemic ultrasound in fetal screening for Down syndrome, trisomy syndrome and neural tube malformation in the second trimester of pregnancy

Objective To explore the application value of serology combined with systemic ultrasound in screening Down syndrome, trisomy syndrome and neural tube malformation fetuses in the second trimester of pregnancy. Methods 5236 single pregnant women who underwent prenatal serology and systemic ultrasound examination in Jinhua Maternal and Child Health Hospital during the second trimester of pregnancy from December 2017 to December 2020 were selected as the study subjects. Serological indicators included free human chorionic gonadotropin (fHCG), alpha fetoprotein (AFP) and unconjugated estriol (uE3). The software was used to calculate the risk value and analyze the karyotype of amniotic fluid cells cultured by amniocentesis in high-risk pregnant women. To compare the diagnostic efficacy of serology, ultrasound single screening and combined screening. Results 56 fetuses with congenital defects were diagnosed by prenatal diagnosis in 5236 pregnant women, the incidence was 1.07%. 288 cases were positive in serology, the positive rate was 5.50%. 116 cases were positive in ultrasound, the positive rate was 2.22%. 82 cases were positive in serology combined with systemic ultrasound, the positive rate was 1.57%. The positive rate and true positive rate of serology, ultrasound, serology combined with systemic ultrasound screening was significantly different (P<0.05). The positive rate of serology combined with systemic ultrasound screening was the lowest, but the true positive rate was the highest. The sensitivity, specificity and positive predictive value of serology and ultrasound screening were significantly higher than those of serology and ultrasound screening, while the false positive rate and false negative rate were significantly lower than those of serology and ultrasound screening (P<0.05). The abnormal rate of pregnancy outcome in high-risk group was 10.98%, which was significantly higher than that in low-risk group (1.36%, P<0.05). Conclusion Compared with single serology and ultrasound screening, the accuracy of screening for fetal neural tube malformation, trisomy syndrome and Down syndrome by serology combined with systemic ultrasound screening in the second trimester of pregnancy is higher. The combination of the two methods can screen most fetal structural malformations and reduce birth defects.