孕中期血清学产前筛查的临床意义分析

Clinical significance of prenatal screening in midtrimester

目的研究孕中期产前筛查中血清标志物甲胎蛋白(AFP)、游离雌三醇(uE3)、人绒毛膜促性腺激素游离β-亚单位(f-βhCG)的临床意义。方法用时间分辨荧光免疫分析技术测定孕妇血清中AFP、UE3、f-βhCG水平,由PE公司提供的唐氏筛查内嵌软件得出产前筛查的风险值。以唐氏综合征(DS)风险大于1∶270为筛查阳性,18-三体综合征,即爱德华综合征(ES)风险大于1∶350为阳性,对筛查出的高危孕妇进行羊水穿刺或B超进行确诊,随访孕妇的妊娠经过及妊娠结果。结果 6379例孕妇中筛查出高危妊娠共576例,其中35岁以下孕妇筛查阳性率为5.19%(285/5484);35岁以上孕妇筛查阳性32.5%(291/895)。对高危组孕妇行羊水穿刺和B超检查共确诊10例,其中5例DS患儿,18-三体综合征患儿3例,NTDs患儿2例。DS检出率达83.3%。结论孕中期血清学筛查是一种较理想的产前检查模式,为了减少假阳性率,要密切随访观察,提高产前筛查的覆盖率能有效降低漏诊率。

Objective To study the clinical significance of prenatal screening of maternal serum markers including alpha-fetoprotein （AFP）,unconjugaied estriol（uE3） and beta subunit of human free chorionic gonadotropin （f-βhCG） in midtrimester.Methods Time-resolved fluorescence immunoassay was employed to detect the maternal serum levels of AFP,UE3 and f-βhCG.Value-at-risk of prenatal screening was obtained by using embedded softerware for Down＇s syndrome screening provided by PE company.Value-at-risk of Down＇s syndrome screening over 1∶270 and that of trisomy 18 syndrome,also named Edward syndrome,over 1∶350 were recognized as positive.Amniocentesis or B ultrasound examination were performed in high-risk pregnant women who had been screened out to confirm the diagnosis and the women＇s pregnant process and results were followed up.Results 576 in 6 379 pregnant women were screened to be high-risk pregnancies.The screening positive rate of 5.19%（285/5 484） was found in pregnant women under the age of 35 years,while 32.5%（291/895） in those over 35 years old.10 cases,including 5 children with DS,3 children with trisomy 18 syndrome and 2 children with NTDs,were diagnosed definitely by amniocentesis and B ultrasound examination in pregnant women in high-risk group,with DS detection rate of 83.3%.Conclusion Serum screening in midtrimester is an ideal prenatal examination mode.Close follow-up observation should be taken to reduce the false positive rate,and improving the coverage rate of prenatal screening may effectively decrease the rate of misdiagnosis.