What You'll Find Out from an NT Scan During Pregnancy

If you recently found out you’re pregnant, you’ll have several doctor appointments and screenings from now until the birth of your baby. Prenatal screenings can identify problems with your health, such as anemia or gestational diabetes. Screenings also can monitor your baby-to-be’s health, and help identify chromosomal abnormalities.

Pregnancy screenings take place during the first, second, and third trimesters. The first trimester screening is a type of prenatal testing that provides your doctor with early information about your baby’s health — namely your baby’s risk for chromosome abnormalities.

A nuchal translucency (NT) scan screens your baby for these abnormalities. This test is typically scheduled between weeks 11 and 13 of pregnancy.

What’s the purpose of an NT scan?

An NT scan is a common screening test that occurs during the first trimester of pregnancy. This test measures the size of the clear tissue, called the nuchal translucency, at the back of your baby’s neck.

It’s not unusual for a fetus to have fluid or clear space at the back of their neck. But too much clear space can indicate Down syndrome, or might show another chromosome abnormality like Patau syndrome or Edwards syndrome.

Individuals born with Down syndrome have an extra copy of chromosome 21. Down syndrome, which can’t be cured, causes developmental delays and distinct physical characteristics.

When is an NT scan scheduled during pregnancy?

The clear space in the back of a developing baby’s neck can disappear by week 15, so an NT scan should be completed in the first trimester.

This test can also include blood work to measure your levels of plasma protein and human chorionic gonadotropin (HCG), a maternal hormone. Abnormal levels of either may indicate a chromosome problem.