Down Syndrome Screening Based on Dried Blood Spots and Cell-free Fetal DNA

Plain-language summary

There are 26,600 Down Syndrome newborns every year in China. The economic burden of this disease is 65,000 USD for lifetime of every patient. The common prenatal screening and diagnosis procedure for fetal chromosomal abnormalities in China is maternal serum prenatal screening in second trimester followed by amniocentesis. The detection rate of MSS is 70%-75% with 5% false positive rate. There are only 13.9% of pregnant women can receive prenatal screening testing in China. It is very urgent that we build a training system and convenient, efficient, cost-effective procedure suitable to rural China. The use of dried blood spots (DBS) technology in conjunction with the second trimester prenatal screening protocol has been proved to be as efficient as serum screening by our previous study. Noninvasive prenatal testing that uses cell free fetal DNA (cff DNA) from the plasma of pregnant women offers a tremendous potential for fetal chromosomal abnormalities. A positive test should be followed by invasive prenatal diagnosis to confirm the test results. Cff DNA is a good supplement to the DBS technology in rural China. A combination of the two methods can increase the screening rate and accuracy without increasing the demand of amniocentesis and cytogenetic test. This procedure with adequate training system should be suitable to rural China. Our study will build a training system for DBS and cffDNA prenatal screening procedure in Pinggu, Beijing. Two thousand pregnant women will receive prenatal screening. DBS sample will be collected in the second trimester, Cff DNA is offered to confirm the positive screening test results, and lastly amniocentesis is offered for confirmation of the test results. All of the pregnancy and neonatal outcomes will be followed. We can estimate the efficiency and cost-effectiveness of DBS followed with cff DNA screening procedure.

Who can participate

What they're measuring

Trial details