Let's know everything about the NT scan (Nuchal Translucency) performed during pregnancy.

The joy you feel when you find out that you are going to become a mother is indescribable, right? But at the same time, there is also a little fear in your heart. "Will my baby be healthy? Will everything go well?" If you have such questions in your mind, it is very normal. Almost everyone who is going to be a mother feels these feelings. So, to check the health of you and your baby, we do various scans and blood tests throughout your pregnancy. Today, we are going to talk about one of the most important, early scans. That is the NT scan.

Simply put, what is this Nuchal Translucency (NT) scan?

Okay, let's explain this very simply. Your little one in your womb has a small amount of fluid under the skin, at the back of his neck. This is a very normal thing for every baby. In medical terms, we call this Nuchal Translucency (NT).

Nuchal (pronounced “nu-kal”) refers to the area at the back of the neck.

Translucency (trans-lu-sun-si) refers to the way light or waves pass through something, that is, its translucent nature.

So, what this NT scan does is use ultrasound technology to measure the thickness of this fluid membrane at the back of your baby's neck. This measurement is taken in millimeters.

Why is this NT scan so important? What does it look for?

Doctors and scientists have found that babies with certain chromosomal abnormalities have a slightly higher amount of this fluid at the back of their necks than a normal baby. So, if the NT value is higher than normal, it's just a hint that there may be some risk for certain conditions.

The main conditions that this scan assesses risk for are:

• Down syndrome (Down syndrome - Trisomy 21)
• Edwards syndrome (Edwards syndrome - Trisomy 18)
• Patau syndrome (Patau syndrome - Trisomy 13)

These are the most common chromosomal abnormalities. In addition, a high NT value can sometimes indicate a risk of a congenital heart condition in the baby.

Also, when performing this scan, the doctor checks whether the development of several basic organs in the baby's body is occurring normally.

At what point during pregnancy is the NT scan done?

This is also a very important question. The NT scan can only be done within a very specific time frame .

That is, between 11 weeks and 13 weeks and 6 days of pregnancy.

In other words, when the baby's crown-rump length is between 45 and 84 millimeters.

There is a special reason for this. After 14 weeks of pregnancy, as the baby grows, the body begins to absorb some of the fluid behind the neck. After that, it is very difficult to get this measurement accurately. That is why it is very important to get the scan within this specified time.

This NT scan is usually done as part of the first-trimester screening test, which means that another blood test is also done along with it.

So what is this first-trimester screening?

This is also known as a "Combined Test." This involves combining the results of the NT scan and a blood test taken from you, and using computer software to calculate whether the baby is at risk. The results obtained when combined with the blood test are more accurate than when the NT scan is done alone.

How do I understand the results? Should I be afraid?

This is the biggest problem that many mothers have. When the results come in, it can be confusing and frustrating. But don't worry. Let's see how this goes.

The doctor will give you the result as a "risk." That is, as a mathematical value. For example, your report may say "1 in 500."

• What does this mean?

This means that if you take 500 mothers with the same results as you (NT score, blood report, age, etc.), only one of them has a chance of having a baby with the genetic condition. That means there is a 499 chance that your baby will be born healthy without any problems.

So, it seems that this is a chance , not a definite decision .

What is a normal NT value?

The NT value also changes a little as the baby grows. But in general, most doctors consider a value of less than 3.0 or 3.5 mm to be normal. However, this value alone is not used to make decisions. The risk is calculated by taking everything together, such as your age and blood test results. So don't just look at a number on the report and come to your own conclusions. Be sure to show it to your doctor and explain it.

What do you do if the result shows that the risk is high?

First of all, take a deep breath and calm down. Not every baby with a high-risk result has a problem. It just means you need to look into it further.

Your doctor will refer you to a specialist or genetic counselor and explain what to do next. Further tests that are usually recommended are:

• Chorionic Villus Sampling (CVS): This is a test done between 11-14 weeks of pregnancy. It involves taking a small piece of tissue from the placenta and examining the baby's chromosomes.
• Amniocentesis: This is a test performed after 15 weeks of pregnancy. A small sample of the amniotic fluid surrounding the baby is taken and tested.

Both of these tests are diagnostic tests. This means that the results are more than 99% accurate. Since there are very few risks associated with these tests, you and your partner can discuss whether to have them with your doctor.

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