NT Scan: Purpose, Procedure & Results

Have you ever heard about an NT scan test?

Well, if you are expecting a baby and in your first trimester of pregnancy, this test is crucial to detect the risk of several chromosomal abnormalities in the developing baby. 

Some common chromosomal abnormalities that can be detected in developing babies are Down’s syndrome (Trisomy 21), Edward's syndrome (Trisomy 18), and Patau syndrome (Trisomy 13), which are congenital conditions. 

Additionally, an NT scan is a diagnostic test that is performed along with other tests to confirm abnormalities and conditions such as neural tube defects, limb abnormalities, abdominal wall effects, and congenital heart disease. Let’s explore this in detail. 

Understanding NT Scan

Whether you say NT scan test or nuchal translucency (NT) test may or may not be recommended in the first trimester of pregnancy (weeks 11 to 14). It is an optional, non-invasive ultrasound in which a fluid-filled space is measured at the back of the neck (nuchal fold) of the developing baby, helping a doctor learn about the fetus’ risk of several congenital conditions. 

Simply put, an NT scan test provides insights into your baby's early development. It is also a screening tool for other anomalies that may lead to genetic or structural conditions. 

Note: Increased thickness may indicate a higher risk of abnormalities or other health issues. Early detection and timely intervention are essential to significantly improve your health outcomes, the growth of the developing baby, and overall well-being to experience a smooth pregnancy. 

NT Scan: Its Purpose in Detail

As hinted above, the NT scan measures the fluid behind the developing baby’s back. A nuchal translucency helps your doctor know if the fetus is at risk of causing complications in the pregnancy, and other tests should be prescribed. 

During the first trimester of pregnancy, which is between 11 and 13 weeks of gestation, the size of the fetus lies between 45 millimeters and 84 millimeters due to the fluid behind the baby’s neck getting reabsorbed by its body after 14 weeks of gestation. 

The purpose of the NT scan is: 

• Helps in early detection: Your doctor is more likely to suggest an NT scan to check for chromosomal abnormalities early in pregnancy. The test can reveal 70% of trisomy 21 or Down syndrome cases. Additionally, some blood tests may also be recommended to improve the accuracy of test results. 
• Poses no risks: An NT scan is a non-invasive method that makes it safer for you and your developing baby’s body. It simply uses ultrasound technology to detect issues. Thus, it poses no risk to you and your would-be baby. 
• If additional testing is needed: If the nuchal translucency test confirms the presence of chromosomal abnormalities detected through the increased thickness of the filled fluid. This further creates a need to order more tests, including blood tests and non-invasive prenatal testing (NIPT), which are needed. 
• Provides insight into the baby's development: For all these reasons, this prenatal care testing provides a complete picture of the baby’s growth in the womb. 
• Assesses risk of genetic conditions: The NT scan test that checks specific pregnancy hormones also helps assess the risk of genetic conditions owing to advanced maternal age (35 or older), multiple miscarriages, or prior stillbirth. 
• Emotional reassurance: Pregnancy is a serious concern for parents, and feeling stressed or anxious is common during the first trimester. A normal NT scan can help expectant parents release tension and give them peace of mind. 

If your doctor has suggested the NT scan, do not delay. It is integral to prenatal care and provides valuable information about your baby’s health. 

Also read: https://redcliffelabs.com/myhealth/pregnancy-test/pregnancy-profile-test-list-check-which-tests-are-important/ 

Who should get an NT scan test?

At the beginning of the blog, it was clear that an NT scan test is optional for pregnant ladies. The test is crucial for pregnant individuals following these categories:

If your age is above 35, anyone over 35 should get a nuchal translucency (NT) test. The test will confirm whether there is a chance of miscarriage, stillbirth, or any other abnormality in the developing baby due to late pregnancy. 

Additionally, if someone has a prior history of pregnancy with a fetal abnormality, they should get tested. 

Having a family history of genetic conditions: Those with a family history of genetic conditions should get tested to learn about the baby’s health and understand the risks and benefits. 

First-trimester pregnancy: Anyone in the first week of pregnancy should get an NT scan test done. 

If you fall under any of these categories, do not delay. Meet your healthcare provider to know if an NT scan is required in your case. 

How is an NT scan test conducted?

The procedure for an NT scan test is straightforward. The test is typically performed in a clinical setting. Before we delve into the clinical procedure for a nuchal translucency test, it is important to know how to prepare for it. 

If your healthcare provider has suggested an NT scan test, you need not make any special preparations. Keeping a few guidelines in mind will surely help you bring the most accurate results:

• Staying hydrated for at least two hours before the test is essential to keeping your bladder full, which will ensure easier-to-read ultrasound pictures. 
• Wear comfortable clothes: To make scanning your lower abdomen easier, wear loose clothes instead of tight ones. 
• Avoid unnecessary medications: If your doctor has asked you to avoid certain medicines before the test, ensure you do. Some drugs can interfere with the test results. 

Consult your doctor before the test if you have doubts or concerns. Your doctor may also order other first-trimester screenings, often called combined sequential screening, to determine a fetus’s risk of congenital conditions. These screenings offer more accurate test results than an NT scan alone. 

The procedure of the NT Scan Test: 

A nuchal translucency (NT) test is often suggested in weeks 11 to 14 during the first trimester of pregnancy. The NT scan procedure usually takes 20-30 minutes and involves these steps: 

• Preparation: 

• First, your healthcare provider will ask you to lie on an examination table. Then, he will apply a clear gel to the abdomen. 
• In the next step, he will move a transducer over your abdomen or inside your vagina, referred to as transvaginal ultrasound, depending upon factors like gestational stage, position of the baby, and your body’s shape to capture clearer images. 

• Measurement: 

• A fluid at the back of a baby’s neck is measured, along with crown-lump length, to confirm gestational change. 

• Completion: 

• Once the NT scan procedure is complete, all the images and measurements will be analyzed, confirming the risk of chromosomal abnormalities. 

Are there any risks involved with an NT scan test?

No. A gel is applied to the site during the NT scan test, and an ultrasound wand moves over it. This causes no discomfort or harm to you or your baby. You may also resume your daily routine. 

Also read: https://redcliffelabs.com/myhealth/radiology/level-2-ultrasound-in-pregnancy-purpose-procedure-and-result/ 

NT Scan Test Results Interpretation

The normal range of an NT scan test is usually under 3.5 millimeters. However, this can vary depending on several factors, such as how far you are in your pregnancy. NT scan test results are categorized into three categories: 

Normal results

If your NT scan test results are normal, the fluid thickness is within normal limits. It is less than the 3.5 mm cut-off for nuchal translucency. 

Abnormal results

Increased thickness fluid beyond 3.5 mm may indicate a higher risk of chromosomal abnormalities or congenital anomalies. Additionally, this may create a need for further diagnostic testing to know the actual status of your baby’s health. 

Risk Evaluation

Suppose the NT scan test results are 1:100 or 1:10 000 000, which indicates chromosomal abnormalities. A risk ratio 1:1000 is low-risk, and any ratio beyond this threshold may indicate further investigation. 

What are the benefits of an NT scan?

Being expectant parents, you are curious to know about the growth of your developing baby, especially if it is a first-trimester pregnancy. The NT scan test measures fluid thickness behind your baby’s back and offers certain benefits: 

• The test aids in identifying potential medical risks, such as chromosomal aberrations or heart conditions, that might develop in a baby. 
• The nuchal translucency ultrasound screening examines many factors, such as the fetus's size, heart rate, structure, and whether more than one fetus is present. 
• The test is 100% safe for both the mother and her child.
• The NT scan is widely available in most prenatal care centers. 
• Additionally, the test provides detailed information for high-risk pregnancies. 

Any abnormalities in the NT scan test result will prompt a specialist to determine if additional tests, such as amniocentesis or chronic villus sampling (CVS), are needed for further evaluation.

Drawbacks or limitations of the NT scan test

The NT scan test is a useful diagnostic tool that can help a healthcare provider and a pregnant mom with the health of a developing fetus. The test is quick, 70% accurate, and risk-free. Still, it has some drawbacks you may like to know:

• The test is non-definitive and may require more tests for confirmation. 
• The test can bring false negative and false positive results. 
• Getting the NT test screening done in the first trimester of pregnancy is vital to receive the most accurate results. 
• The test only focuses on chromosomal abnormalities and thus is likely to miss other potential issues. 

Redcliffe Labs and Nuchal Translucency Test

An NT scan test can help determine the possibility of the fetus having a congenital or genetic condition. In case of abnormal NT scan results, more tests are needed. The healthcare provider suggests the test early in the first trimester of pregnancy to identify the risk of chromosomal abnormalities, empowering you to make well-informed decisions about your baby’s health. 

Leave no stone unturned to increase your chances of having a healthy baby. Discuss your reports with your healthcare provider to understand the specific test results. 

FAQ: 

1. Why do you need an NT scan?

You may need an NT scan test if you are above 35 and have already experienced miscarriages in the past. The test helps detect chromosomal abnormalities such as Down’s Syndrome in the baby, a family history of a genetic condition, or worries about having a smooth pregnancy. 

2. When is an NT scan done?

A doctor prescribes an NT scan test in the first trimester of pregnancy, done during the third month. It is an optional screening that gives clearer results in the case of a single child. 

3. Can I detect gender from an NT scan?

No, an NT scan does not help you with the gender information of your child. It is a simple test that detects chromosomal abnormalities in the first trimester of pregnancy. 

4. Is an NT scan compulsory for pregnant individuals?

No, the NT scan is not compulsory for pregnant females. It is mandatory for expectant parents who seek assurance about their child’s growth.