Test Overview

The nuchal (say "NEW-kuhl") translucency screening is a test done during pregnancy. It uses ultrasound to measure the thickness of the fluid buildup at the back of the developing baby's neck. If this area is thicker than normal, it can be an early sign of Down syndrome, trisomy 18, or heart problems.

The test is done between 10 and 13 weeks of pregnancy. It may be done as part of the first trimester screening test or the integrated screening test.

This test shows the chance that a baby may have a certain problem. It can't show for sure that a baby has a problem. You would need a diagnostic test, such as chorionic villus sampling (CVS) or amniocentesis, to find out for sure if the baby actually has a problem.