Clinical analysis of the combined screening of AFP,UE_3,β-HCG on diagnosis for the Down syndrome at the second trimester of pregnancy

BACKGROUND To study the method of prenatal screening for Down syndrome at the second trimester of pregnancy and main factors of affecting its value-at-risk. CASE REPORTS The value of AFP ,UE3,β-HCG in serum of 950 cases of pregnant women at 14～20 weeks were detected by the automated Chemiluminescence Immunoassay System,and the value-at-risk was analyzed by using analytical software provided from Beckman Corporation in America. The risk-rate was 1∶380 as the cut-off point to analyze risk status in 950 cases of second trimester fetuses.10 of second trimester fetuses were over 1∶380 risk rate,in which 5 cases were performed amniocentesis and 1 case was diagnosed to the Down syndrome by karyotype analysis of chromosome in amniotic fluid,the other 5 cases refused invasive procedures,but diagnosed negative after childbirth,and positive rate was 10.0%. DISCUSSION The combined screening of AFP,UE3,β-HCG in serum is ideal prenatal screening model of diagnosis for the Down syndrome.