The analysis on the screening results of second trimester prenatal of 7135 cases in Xian.

Objective:Down′s syndrome screening,minimizing the incidence of birth defects.Methods:BHP9504-based microplate luminescence analyzer extracted from 13 to 21+0 weeks of gestation serum free β-HCG and AFP levels,combined with age,gestational age and weight and other factors and then the matching software to calculate risk rate and evaluation.Results:7135 cases of pregnant women through prenatal screening for Down syndrome were detected in 276 pregnant women at high risk rate of 3.87%.Age≥35 years of age(15/33) 45.45% detection rate was significantly higher than other age groups.Conclusion:Maternal serum markers can significantly reduce the trauma of sexual proportion of pregnant women for prenatal diagnosis of Down′s children to reduce the birth of larger significance.