To Investig The Value Of Noninvasive Prenatal Testing In The Prenatal Diagnosis Of Fetal Chromosomal Aneuploidy

Objective:To explore the feasibility that the High-risk Serum Screening for Down Syndrome and advanced maternal age women can choose non-invasive prenatal testing,and then make a decision about further prenatal diagnosis then according to the results of NIPT.Methods:Analysis of outpatient pregnant women in prenatal diagnosis center of our hospital.These pregnant women were divided into four groups: Group A 1919 cases for the advanced maternal age women who informed consent to choose NIPT;860 cases of group B for the High-risk Serum Screening for Down Syndrome who informed consent to choose NIPT;607 cases of group C for the advanced maternal age women who choose prenatal diagnosis directly;Group D 1628 cases for the advanced maternal age women who choose prenatal diagnosis directly.To analyze the accordance rate of NIPT in diagnosing fetal chromosomal aneuploidy(T21 ?T18 ? T13)with invasive prenatal diagnosis between group A and group B.To analyze the positive rate of the chromosomal aneuploidy(T21,T18,T13)between group A and group C,group B and group D and make statistical analysis.Results:1.In group A,41 cases were positive,the positive rate is2.14%.Among which 15 cases were T21,8 cases were T18,15 cases T13,Others were sex chromosome abnormalities,microdeletion syndrome,and trploid.36 cases chose invasive prenatal diagnosis,4 cases were T21,6 cases were T18,1 cases were T13,7 cases were sex chromosome abnormalities and 1 case was microdeletion syndrome,the rest were normal.4 cases of sex chromosome abnormalities refused to invasive prenatal diagnosis,there were 3 cases had been delivered whose appearance have no obvious abnormalities so far,one another had lost communication.1 case refused to invasive prenatal diagnosis and termination of pregnancy,whose NIPT report shows T18 high risk,there are multiple structural deformities in the late pregnancy.2.In group B,8 cases were positive,the positive rate was 0.93%.Among which T21 were 2 cases,T13 was one case,.3 cases were sex chromosomal abnormalities and 2 case were trploid.7 cases chose invasive prenatal diagnosis,2 cases were T21,T18,T13 were positive,1 cases of sex chromosome abnormalities,the rest are normal.One case of non-prenatal testing suggested sex chromosomal abnormalities,fetal death within the uterus during mid-pregnancy.3.In group C,16 cases were positive,the rate of positive was 2.64%.A mong of these,12 cases were T21?T18 and T13.Other chromosome abnormalities were sex chromosome abnormalities,chimeras and MMS.4.In group D,23 cases were positive,the rate of positive was 1.3%.Other chromosome abnormalities were sex chromosome abnormalities,chimeras and MMS.5.There was no significant difference in chromosome abnormality(T21,T18,T13)between group A and group C;There was no significant difference in chromosome abnormality(T21,T18,T13)between group B and group D.Conclusion : High-risk Serum Screening for Down Syndrome and advanced maternal age can choose non-invasive prenatal testing at first,and then make a choice to undergo further prenatal diagnosis according to the results of NIPT.It is important to clinic.