Down′s Syndrome antenatal screening and diagnosis were analyzed.

Objective: To improve the screening rate of Down′s Syndrome(DS) by combination of ultrasonic B examination in early pregnancy and serologic analysis in middle pregnancy.Methods: Detectong nuchal translucency thickness(NT) of early pregnant women(11-14weeks) by ultrasonic B and examination serum AFP and F-β-HCG of middle pregnant women(14-20~(+6)weeks) by biochemical assay.After the examination,results were calculated with special software,part of the factors such as age,weight and pregnant time that may possibly affect the results were analyzed and rectified.Hereditary consultation was provided for the high risk women,amniocentesis diagnosis was done with their agreement.Each pregnant woman was followed until parturition.Results: 4376 pregnant women accepted antenatal screening,43 cases of them were at high risk with NT by ultrasonic B,252 cases were detected at high risk with DS by serologic analysis in middle pregnancy,78cases were at high risk with NTD.Among 4376 cases,4cases were DS,other chromsome abnormal 2cases;12cases were defect fetal decreased but their chromsome normal.Conclusion:Combination of ultrasonic B in early pregnancy and serum analysis in middle pregnancy were effective and practicable to screen congenital defect especially DS.With antenatal diagnosis,the birth rate of defect fetal decreased.