A follow-up analysis of prenatal screening in 3651 cases on middle period pregnancy

Objective:To explore the clinical application and value in prenatal screening of Down's syndrome and open nervous tube defect on middle period pregnancy.Methods: Serum samples were collected from 3651 pregnant women on middle period pregnancy(15-20+6week) and free-β-human chorionic gonadot ropin(free-β-hCG) and alphafetoprotein(AFP) level were determined by time-resolved fluoroimmunoassay(TR-FIA,or DELFIA) method.Risk2T was used to calculate the risk rate of Down's syndrome(DS),13/18 trisomy syndrome and open nervous tube defect(ONTD).Results: The calculated results show that 241,20 and 30 cases were with high risk of DS,13/18 trisomy syndrome and ONTD in 3651 test samples,respetively.After-birth visit on the high-risk pregnant women indicated that 5 births suffered DS,no birth suffered 13/18 trisomy syndrome and 2 births suffered ONTD.Among 3390 low-risk cases of DS,there was also one birth suffered DS.Conclusion: The results in this paper indicate that prenatal screening of middle period serum of pregnant women can reduce the risk of birth defects incidence.