Down analysis of 7859 cases of second trimester screening and prenatal diagnosis in Huaihua Region.

Objective: To investigate the second trimester prenatal diagnosis of Down's screening and detection of fetal chromosomal abnormalities and the clinical value of adverse outcomes of pregnancy.Methods:The time-resolved fluorescence immunoassay 7,859 cases of second trimester(14-20 weeks)women with serum markers triple regimen(hAFP+free-β-hCG+uE3)detection.Application software to calculate screening results Multical trisomy 21,trisomy 18 syndrome and open neural tube defects risk(rish)probability.For high-risk pregnant women by genetic counseling,informed consent,voluntarily choose to prenatal diagnosis,the pregnancy at 18-24 weeks amniocentesis under ultrasound guidance,taking amniotic fluid culture,fetal karyotype analysis.And continue to track the fetal and maternal conditions.Results:7859 cases of pregnant women,screening to high risk of 732 cases,positive rate of screening for Down 7.65%(601/7859).367 cases in which receiving prenatal diagnosis of amniotic fluid or umbilical cord puncture,screening high-risk pregnant women accounted for 50.13%(367/732);found 16 cases of fetal chromosomal abnormalities,abnormal detection rate of 4.36(16/367),6 cases of Down′s syndrome,5 cases of 18-trisomy,Turner′s syndrome in 4 case.1case of chromosome 9 pericentric inversion.Down′s screening of high risk and low risk of adverse pregnancy outcomes were 6.15% and 1.46%,was significantly different(0.05).Conclusion: The abnormal second trimester prenatal screening for fetal to predict adverse pregnancy outcomes and effective index.Cord blood with amniotic fluid culture or cultivation of prenatal diagnostic techniques and methods to prevent birth defects of children bom to improve the quality of the population has important clinical value.