As an expectant parent, it’s natural for you to worry about your baby’s health. Fortunately, several tests are performed during pregnancy to ensure your baby’s proper growth and well-being. One such screening test is the nuchal translucency test done during the first trimester. This blog will delve deeper into the details of the nuchal translucency test, its purpose, procedure, and result.
What is a nuchal translucency test?
A nuchal translucency test (or NT scan) is an ultrasound test performed during the first trimester of pregnancy to measure the amount of fluid filled behind your baby’s neck. This non-invasive scan can help your doctor determine your chances of carrying a baby with chromosomal abnormalities, such as Down syndrome and other genetic disorders.
What does nuchal translucency scan for?
A nuchal translucency scan examines the nuchal fold, a space behind your baby’s neck filled with fluid. This test helps your doctor detect any abnormal fluid accumulation in this region, which could indicate chromosomal or genetic conditions in your baby, such as Down syndrome (trisomy 21), Patau syndrome (trisomy 13), Edwards syndrome (trisomy 18), or an increased risk of congenital heart conditions.
Furthermore, the NT scan checks basic anatomical structures and identifies abnormalities that may increase your unborn baby’s risk for genetic or structural issues.
When is an NT scan performed?
Your doctor may perform an NT scan as a part of a first-trimester screening test, typically between 11 and 13 weeks of pregnancy or when your baby measures between 45 millimeters and 84 millimeters from the crown (top of their head) to rump (bottom of their torso). After the 14th week of pregnancy, the fluid behind your baby’s neck gets reabsorbed by the body, making it difficult to receive accurate results.
How is the nuchal translucency scan done?
The nuchal translucency scan can be done through your abdomen (transabdominal) or vagina (transvaginal), depending on several factors, such as the stage of your pregnancy, your body shape, and the available equipment.
During a transabdominal scan, your doctor will apply some gel and gently move the ultrasound probe across your abdomen. Your baby’s pictures will appear on the monitor screen, and the measurement of your baby’s nuchal fold will be taken. Before the scan, your doctor might advise you to drink plenty of fluids so your bladder is full, making it easier to see inside your uterus.
During a transvaginal scan, your doctor gently inserts a tiny, lubricated ultrasound probe into your vagina to view your baby’s image and measure the nuchal fold. Since the probe is closer to your uterus, this scan can give detailed images. The transvaginal method isn’t usually painful but could feel a little uneasy.
It is essential to remember that both ultrasound tests do not hurt you or your unborn baby or raise your chance of miscarriage (pregnancy loss).
What do the results mean?
Since an NT scan is performed as a part of the first-trimester screening test, your doctor may combine the results of the other tests to determine your baby’s risk of congenital conditions. Mostly, you will be requested to take an additional blood test to improve the result’s accuracy.
If your test result shows a high-risk (positive), your doctor might recommend further diagnostic tests, such as chorionic villus sampling (CVS) or amniocentesis, to offer a definitive result. It’s essential to remember that a positive result from an NT scan provides an estimation and does not confirm the presence of congenital conditions in your baby. You still have a chance of having a healthy baby.
If you wish to learn more about the scan or its result or have concerns, consult your doctor for personalized guidance.
