孕中期超声检测胎儿肱骨股骨长度筛查唐氏综合征的研究

Study of second trimester ultrasonographic fetal humerus and femar length in prenatal screening for Down's syndrome

目的探讨超声检测孕中期胎儿肱骨股骨长度对产前筛查唐氏综合征的临床价值。方法对2004年1月至2008年10月在本院行产前血清学筛查唐氏综合征高风险孕妇201例胎儿行超声测量其肱骨长度(HL)、股骨长度(FL),所有胎儿经超声引导下取脐带血行染色体核型分析。结果201例血清学筛查唐氏综合征高风险孕妇,经超声引导下脐带穿刺取脐血行染色体核型分析,诊断为唐氏综合征11例,染色体正常胎儿190例。唐氏综合征胎儿的81%(9/11)HL、72%(8/11)FL较同孕龄染色体正常胎儿短2SD以上。结论胎儿HL、FL短对产前超声筛查唐氏综合征具有临床价值,如能结合血清生化指标综合分析判断唐氏综合征风险,将会减少不必要的创伤性产前诊断手术。

Objective To investigate the clinic value of ultrasonographic fetal humeral length and femoral length examination as a screening for Down＇ s syndrome. Methods 201 singleton pregnancies of second trimester at high risk of Down＇ s syndrome,which underwent prenatal serological screening for Down＇s syndrome at our hospital from January 2004 to October 2008 ,were performed with ultrasonographic measurement of fetal humeral length（HL） and femoral length（FL）. Fetal blood sampling by cordocentesis under the guidance of ultrasound was performed for karyotype analysis in all fetuses. Resuits 201 pregnancies at high risk of Down＇s syndrome underwent fetal blood sampling by cordocentesis under the guidance of ultrasound for karyotype analysis. Among these fetuses, 11 fetuses were Down syndrome, 190 were fetuses of normal ehromosomes. HL in 9 Down＇s syndrome （ 81% ,9/11 ） and FL in 8 （72%, 8/11 ） were 2SD or more shorter than those with norreal chromosomes over the same gestational age. Conclusion Ultrasonographic measurement of fetal HL and FL appears to be valuable for prenatal screening for Down＇ s syndrome and would reduce unnecessary invasive procedures of prenatal diagnosis if combined with serum biochemical indicators to determine the risk of Downg syndrome.