唐氏综合征筛查在高龄孕妇产前诊断中的应用价值

目的探讨唐氏综合征（DS）筛查在高龄孕妇产前诊断中的意义。方法选择台州医院在2006年1月到2011年12月进行产前筛查的高龄孕妇。DS筛查采用时间分辨免疫荧光分析法检测孕中期孕妇血清标志物甲胎蛋白（AFP）和人绒毛膜促性腺激素（游离t3-hCG），通过Multicalc和Risks2T风险评估软件进行风险评估。高龄孕妇行羊膜腔染色体检查，并追踪妊娠结局。数据处理采用SPSS13．0统计软件，率的比较采用Y。检验，P〈0．05为差异有统计学意义。结果本研究的4187例高龄孕妇中21-三体发生率0．76％（32／4187）、18-三体发生率0．31％（13／4187）和13三体发生率0．02％（1／4187）。高龄孕妇中行DS筛查1076例，其中高风险孕妇648例，21三体发生率1．76％（11／626）和18-三体发生率15．15％（5／33）；低风险孕妇428例，检出其他染色体异常5例。两组数据比较差异有统计学意义（P〈0．01）。结论高龄孕妇行无创性产前筛查联合羊膜腔染色体诊断技术，其诊断效率明显高于未行产前筛查者，尤其是对于提高18-三体检出率具有重要临床意义。

Evaluation on the practical value of prenatal screening for Down syndrome among women of advanced maternal age

Objective To assess the practical value of prenatal screening for down syndrome among pregnant women of advanced maternal age. Methods Pregnant women with advanced maternal age who did prenatal screening for Down syndrome （DS） in Taizhou hospital from January 2006 to December 2011 were selected and tested for the serum levels of AFP and free 13 HCG during the second trimester by time-resolved immuno- fluorescence method. Final diagnosis was confirmed by chromosome examination of amniotic fluid cell or allan toic venous blood cells. The diagnostic results were compared with the follow-up outcome of the pregnancies. Results Among 4187 women of advanced maternal age, 32 were found to have 21-trisomy （0. 760/oo） . Also, there were 13 and one who carried 18 trisomy （0.31%） and 13-trisomy （0.02） .Out of 1076 women screened for DS, 648 were at high risk with the incidence of 1.76G for 21-trisomy and of 15.15% for 18-tri- somy. Only 5 women were found to have other chromosomal abnormalities among 428 women with low risk. The difference was statistically significant between the two sets of data （P〈0.01）. Conclusions Non- invasive prenatal screening in women of advanced maternal age combined with amniotic chromosome examina- tion may significantly increase the diagnostic efficiency for DS especially for 18-trisomy detection.