Researchers have found that a blood test carried out between 10 and 14 weeks of pregnancy is more effective in detecting Down syndrome and two other chromosomal abnormalities compared to non-invasive screening procedures.

Babies with Down syndrome, also known as trisomy, have an extra copy of chromosome 21, which causes what used to be called mental retardation. They also have a number of characteristic physical features, including short stature, a broad face, slanted eyes and a short neck. They also have intellectual and some physical disabilities.

Like Us on Facebook

Experts detailed how a cell-free DNA blood test was able to correctly identify fetuses with Down syndrome and had results that were confirmed through newborn exams and prenatal or postnatal gene analysis.

Researchers followed nearly 16,000 women and their pregnancy outcomes using fetal DNA found in pregnant women's blood to determine the presence of Down syndrome and other less common abnormalities.

Cell-free DNA blood tests identified 38 fetuses with Down syndrome while standard screening only spotted 30 cases. An ultrasound to detect levels of nuchal fold fluid in the back of the neck was also done to complete the blood test screening. Excessive amounts of fluid can hint at Down syndrome.

The cell-free blood test also saw a smaller number of false positives than conventional pregnancy screening. It didn't identify all the abnormalities the other procedures did.

Down syndrome is caused by an extra copy of chromosome 21 while Edwards syndrome is the result of three instances of chromosome 18.

Details of the new findings appeared in New England Journal of Medicine.

TagsNew DNA Blood Tests Offer Better Detection of Down Syndrome, Down syndrome, Blood test, DNA blood tests, chromosome 21, Edwards syndrome, Patau syndrome, Pregnancy, pregnant women, chromosomal abnormalities