Noninvasive Prenatal Testing In The Clinical Application Evaluation Of Down’s Syndrome

Purpose: To investigate the clinical application efficiency of Noninvasive prenatal testing and the traditional standard screening in screening for Down’s syndrome Method: The research mainly through the retrospective study,based on the principle of patients’ informed,voluntary,signed informed consent,in August 2014 to July 2014,our hospital prenatal diagnosis center line of noninvasive prenatal detection of 1209 cases of pregnant women as the research object,by genomics companies extracting cell-free fetal DNA in maternal blood,using the second generation of high flux large-scale genome sequencing technology,in the middle of our prenatal diagnosis center line at the same time pregnant serologic screening,tips for test result was abnormal,timely call an amnio or umbilical cord blood puncture diagnosis,detection results negative telephone follow-up were analyzed.Result: 1 by studying the MSS low-risk pregnant women,gestational age older than 35 years old and 89% of whom gestational age less than 35 years old Pregnant woman found that,regardless of the pregnant women ages,noninvasive prenatal detection compared with the traditional serologic screening,NIPT in the sensitivity of the screening for down syndrome was 99.9%,95% confidence interval 99.8% to 100%(P < 0.001),the sensitivity of the MSS screening for down syndrome was 73.1%,95% confidence interval,53.7 to 95%(P = 0.035),the difference was statistically significant.2 through the study of 176 cases of elderly pregnant women prenatal diagnosis center screening DS,4 cases were found screening high-risk,through an amnio karyotype analysis confirmed 3 cases for T21-three body,appear 1 period is positive,follow-up the results did not see abnormalities,the 21-three body detection rate of 1.70%.In the same period,296-gestational age older than 35 years old do an amnio karyotype analysis,only 4 cases were diagnosed as T21-three body,detection rate was 1.40%,there was no statistically significant difference.3 1085 < 35 years old pregnant women accept NIPT,including 3 cases of high risk,2 cases after amniotic fluid puncture in diagnosis,clear T21-three body syndrome,1 period is positive,the sensitivity of 66.7%,the specific degree of 99.9%,positive predictive value 66.7%,negative predictive value of 99.9%;815 cases of pregnant women in traditional serologic screening negative result,NIPT detected in 1 DS,MSS low-risk pregnant women down’s syndrome rate was 1.22 ‰。 Conclusion: 1 in screening for down syndrome,NIPT compared with traditional MSS screening,the false positive of NIPT is markedly lower than the traditional MSS screening,and has high positive predictive value.2 In gestational age older than 35 years women,screening for children with DS NIPT can be widely used,improve the detection rate,effective screening for pregnant women and their families by fear intervention to refuse to prenatal diagnosis of patients,reduce the DS was born.3 NIPT and MSS in the actual clinical application,for < 35 and MSS screening results in low risk pregnant women,NIPT in the detection of down syndrome has higher sensitivity,specificity,positive predictive value,negative predictive value,without damage and high accurate prenatal detection method.