Value of prenatal screening during the second trimester of pregnancy

Objective:To explore the value of prenatal screening in prenatal diagnosis of women during the second trimester of pregnancy.Methods:A total of 2 880 women during 16-20 gestational weeks received prenatal screening from January 2006 to September 2009,the serum levels of alpha fetoprotein(AFP),free human β gonadotropin(F-βHCG),and free estriol were detected,the risk index was evaluated combined with other factors,such as age and body weight.The high risk pregnant women underwent amniocentesis,then they were diagnosed definitely by chromosomal karyotype test of amniotic fluid cells.Results:A total of 2 880 pregnant women received prenatal screening,five pregnant women were found with high risk of Down's syndrome,after chromosomal karyotype test of amniotic fluid cells,two pregnant women were diagnosed definitely;two pregnant women were found with high risk of trisomy 18,after chromosomal karyotype test of amniotic fluid cells,one pregnant woman was diagnosed definitely;two pregnant women were found with high risk of neural tube defect,after chromosomal karyotype test of amniotic fluid cells,two pregnant women were diagnosed definitely.All the pregnant women were followed up until the birth of the fetuses,one pregnant woman with negative result of prenatal screening gave birth to a infant with Down's syndrome.Conclusion:Prenatal screening can improve the detection rate of the infants with congenital defects,which is an effective measure to improve the quality of birth population.