Detecting Down Syndrome More Accurately
A fairly new non-invasive test given to women during the first trimester can determine Down syndrome more precisely.
The test, called cell-free fetal DNA testing, can "detect more than 99% of Down syndrome cases in singleton pregnancies, with a very low false positive rate of less than 0.1%," reports Science Daily.
According to the Mayo Clinic, the test involves analyzing a pregant woman's blood after 10 weeks of gestation. Researchers look for fetal DNA in the mom's blood to see if there is a third copy of chromosome 21, an indicator that a child may have Down syndrome. (Down syndrome is also called trisomy 21 because of the extra chromosome.) Moms who are at a higher risk of giving birth to a child with DS are usually given the test.
Although the test yields better results, other forms of testing may be required to confirm a Down syndrome diagnosis. These more invasive tests include amniocentesis (amniotic fluid is withdrawn from the uterus), chorionic villus sampling (cells are removed from the placenta), and cordocentesis (blood is taken from a vein in the umbilical cord).
Sherry Huang is a Features Editor for Parents.com who covers baby-related content. She loves collecting children's picture books and has an undeniable love for cookies of all kinds. Her spirit animal would be Beyoncé Pad Thai. Follow her on Twitter @sherendipitea
Image: Down syndrome/Trisomy 21 test results via Shutterstock