妊娠中期HCG与AFP联合筛查非高龄孕妇唐氏综合征的价值分析

The Value of HCG and AFP in the Second Trimester in Screening for Down Syndrome in Non-elderly Pregnant Women

目的探讨妊娠中期(孕14~20周)检测血清绒毛膜促性腺激素(human chorionic gonadotropin,HCG)联合甲胎蛋白(alpha fetoprotein,AFP)对筛查唐氏综合征(down syndrome,DS)的价值。方法选取2015年1月至2017年6月在重庆市綦江区妇幼保健院开展产前筛查的孕14~20周非高龄孕妇共5 053例,进行血清HCG和AFP检查。结合孕妇一般资料,利用筛查软件确定DS高风险孕妇,所有孕妇均持续追踪至妊娠结局。结果筛查结果显示,DS高危孕妇281例,占5.56%,≥30岁孕妇的筛查阳性率明显高于<30岁孕妇。DS高危孕妇中确诊DS 4例,低危孕妇中确诊DS 2例。HCG和AFP联合检查方案的灵敏度66.7%,特异度94.51%,假阳性率5.49%,假阴性率33.3%,阳性预测值1.42%,阴性预测值99.96%。结论孕中期血清HCG和AFP能够有效筛查出DS高风险孕妇,对降低DS胎儿出生率有一定价值。但其筛查灵敏度及特异度均有所欠缺,可能仍需探寻更可靠的产前筛查方案。

Objective To investigate the value of serum human chorionic gonadotropin （HCG） and alpha fetoprotein （AFP） in screening for Down syndrome （DS） in women in the second trimester （14-20 weeks）. Methods A total of 5 053 non-elderly women at 14～20 weeks of pregnancy undergoing the prenatal screening in Chongqing Qijiang District Maternal and Child Health Care Hospital from January of 2015 to June of 2017 received the detection of serum HCG and AFP. Combined with the general information of those pregnant women, the DS high-risk pregnant women were identified by the screening software and all the pregnant women were continuously followed up until the pregnancy outcome. Results The screening results showed that there were 281 DS high-risk pregnant women accounting for 5.56%. The positive rate in the cases no less than 30 years old was much higher than that in the cases less than 30 years old. 4 DS cases were diagnosed in the DS high-risk pregnant women and 2 DS cases were diagnosed in the low-risk pregnant women. The sensitivity was 66.7%, the specificity was 94.51%, the false positive rate was 5.49%, the false negative rate was 33.3%, the positive predictive value was 1.42%, and the negative predictive value was 99.96% in the joint screening scheme with HCG and AFP. Conclusion The levels of serum HCG and AFP in the second trimester can effectively screen for the DS high-risk women, which is of some value in reducing the DS fetal birth rate. However, the screening sensitivity and specificity are not good enough, so further researches should be made to explore more reliable prenatal screening schemes.