Application of serum AFP and free-β HCG in the pregnant metaphase for prenatal screening

Objective:To evalauate the practical value of detecting serum AFP and free-β HCG in the pregnant metaphase for prenatal screening.Methods: Auto time-resolved fluoroimmunoassay system was used to detect the matermal serum AFP and flee-β HCG in 3384 peregnant women at about 15～20 weeks of gestaion,Down's syndrome,NTD,Edwards syndrome risk value was calculated with Multicalc software,their cut-off were 1∶270,1∶250,1∶350 separately.The pregnant women whose value are higher than or equal to cut-off would be at high risk and need to exclude fetal abnormal karyotype comning diagnoses with ultrasonic B examination,amniocentesis or fetal blood.Results:3384 pregnant women accepted antenatal screening,177 case of them were detected at high risk and positive rate was 4.3%.In 177 case.131 of them were at high risk with Down's syndrome,7 case with 18 triploid syndrome,21 case with NTD.In the high risk pregnant women,11 case with fetal anmormal chromosome were found by amniotic fluid or fetal blood culture,8 case with anmormal fetal were found by ultrasonic B.Conclusion: Serum AFP and free-β HCG level of pregnant women were effective indexes to screen abnormal fetal.