You'll have plenty of tests over the next nine months to make sure both you and baby are progressing well, and this is one you can expect to have in your first trimester. The nuchal translucency screening (also known as the NT scan or nuchal fold scan) is basically a special (totally painless) ultrasound that tests baby primarily for Down syndrome. Either the ultrasound technician or sometimes your doctor will lather your belly with gel and run a transducer wand over it, which emits sound waves that then become electrical signals, and voilà!, you’ll see baby’s picture pop up on a nearby screen. While you're absorbed with that, the technician or your OB will examine the back of baby’s neck on the screen. If this area is thicker than normal, it can be an early warning sign of Down syndrome, Trisomy 18 or 13 (other chromosomal disorders) as well as certain congenital heart defects.
Make an appointment with your doctor sometime between 10 and 14 weeks for this test. You'll probably undergo a combined screening, including a serum test to check your blood. Together, these two tests determine whether baby has a genetic defect. Remember this: although a nuchal translucency test might show increased thickness in baby’s neck, your blood test results could rule out Down syndrome. In this scenario, there is the possibility of a slight heart defect, and your doctor will most likely run further tests on baby’s heart to find out more details.