NIPT Test: A Safe Way to Screen for Genetic Conditions in Pregnancy

What Is the NIPT Test?

The NIPT test, or noninvasive prenatal testing, is a simple blood test that screens for chromosomal abnormalities in a developing baby. This advanced prenatal screening analyses fragments of the baby's DNA present in the mother's bloodstream to assess the risk of certain genetic conditions. The NIPT test is considered a safe and highly accurate way to gain important insights into foetal health without posing any risk to the pregnancy.

How Does NIPT Work?

During pregnancy, small fragments of the baby's DNA circulate in the mother's bloodstream. These DNA fragments, known as cell-free foetal DNA (cffDNA), are derived from the placenta and closely resemble the baby's genetic material. The NIPT test works by analysing the cffDNA in the mother's blood sample to detect any potential chromosomal abnormalities. By comparing the relative amounts of DNA from different chromosomes, NIPT can determine if there are any extra or missing copies, which may indicate a genetic condition.

What Are the Conditions Detected by NIPT?

The NIPT test primarily screens for the following chromosomal abnormalities:

• Trisomy 21 (Down syndrome): Caused by an extra copy of chromosome 21.
• Trisomy 18 (Edwards syndrome): Associated with an additional copy of chromosome 18.
• Trisomy 13 (Patau syndrome): Occurs when there is an extra copy of chromosome 13.
• Sex chromosome aneuploidies: Abnormalities in the number of X or Y chromosomes, such as Turner syndrome (45,X) or Klinefelter syndrome (47,XXY).

Some NIPT tests may also screen for other genetic conditions like microdeletion syndromes, but this varies by the specific test and laboratory.

Also Read: Double Marker Test: What it is and What Happens During it

What the NIPT Test Does Not Detect?

While the NIPT test is a powerful screening tool, it is essential to understand its limitations. NIPT cannot detect all possible genetic disorders or birth defects. It primarily focuses on specific chromosomal abnormalities and does not provide information about other genetic conditions caused by single gene mutations or structural abnormalities in the chromosomes. Additionally, NIPT cannot detect neural tube defects, such as spina bifida, or physical birth defects like heart malformations or cleft lip and palate.

When Is NIPT Recommended?

The NIPT test is typically recommended for pregnant women who are at higher risk of having a baby with chromosomal disorders.

This includes:

• Women aged 35 years or older at the time of delivery
• Those with a personal or family history of chromosomal conditions
• Women with abnormal results from other prenatal screening tests
• Pregnancies conceived through in vitro fertilization (IVF) with donor eggs

However, the NIPT test is available to all pregnant women, regardless of age or risk factors. It is generally performed after the 10th week of pregnancy, as there needs to be sufficient foetal DNA in the mother's bloodstream for accurate analysis.

NIPT vs Other Prenatal Tests

Compared to traditional prenatal screening methods, such as the first-trimester combined screen or the quad screen, the NIPT test offers several advantages:

• Higher accuracy: NIPT has a higher detection rate and lower false-positive rate for chromosomal abnormalities, particularly Down syndrome.
• Earlier results: NIPT can be performed as early as 10 weeks into pregnancy, providing expectant parents with information sooner than other screening tests.
• No risk to the baby: Unlike invasive diagnostic tests such as amniocentesis or chorionic villus sampling (CVS), NIPT does not carry a risk of miscarriage or injury to the foetus.

However, it's important to note that NIPT is a screening test, not a diagnostic one. Abnormal NIPT test results require confirmation through invasive testing.

How Accurate Is the NIPT Test?

The NIPT test boasts high accuracy rates, particularly for the detection of Down syndrome. Studies show that NIPT can detect over 99% of cases of trisomy 21, with a false-positive rate of less than 0.1%. The accuracy for detecting trisomy 18 and trisomy 13 is slightly lower but still above 90%. However, it's crucial to remember that NIPT is a screening test, meaning it cannot definitively diagnose a genetic condition. Abnormal results should always be confirmed with diagnostic testing.

Is NIPT Safe For The Baby?

Yes, the NIPT test is completely safe for both the mother and the baby. Unlike invasive procedures like amniocentesis, which carry a small risk of miscarriage, NIPT only requires a blood draw from the mother. There are no needles or probes inserted into the uterus, and the test does not pose any physical risk to the foetus. This makes NIPT an attractive option for women who want to gain information about their baby's health without invasive testing.

Is it Necessary to Get the NIPT Test During Pregnancy?

While the NIPT test is highly accurate and safe, it is not mandatory for all pregnant women. The decision to undergo NIPT is a personal choice that should be made in consultation with your doctor, considering your individual risk factors and preferences.

Who Should Consider Taking the NIPT?

The NIPT test is particularly recommended for women who are at higher risk of having a baby with chromosomal abnormalities. This includes women over the age of 35, those with a family history of genetic disorders, or those who have had abnormal results on other prenatal screening tests.

How to Prepare for the NIPT Test?

No special preparation is needed for the NIPT test. You can eat and drink normally before the blood draw. However, it's important to schedule the test at the appropriate time in your pregnancy, usually after 10 weeks gestation. Your doctor will guide you on when to schedule the test based on your individual circumstances.

What to Expect During the NIPT Test?

The NIPT test is a simple blood test performed at a doctor's office or a diagnostic laboratory. A phlebotomist will cleanse an area on your arm and use a needle to draw a sample of blood from a vein. The process usually takes just a few minutes, and you may experience mild discomfort or bruising at the needle site. The blood sample is then sent to a laboratory for analysis, and results are typically available within a week or two.

Understanding NIPT Results

NIPT test results are reported as either "low risk" or "high risk" for screened chromosomal abnormalities.

• A low-risk result means the chance of the baby having one of the targeted disorders is very low, offering reassurance to expectant parents. However, it’s important to note that a low-risk result does not guarantee a baby without genetic conditions, as NIPT only screens for specific abnormalities.
• A high-risk result indicates an increased chance of a chromosomal disorder. In such cases, your doctor will recommend follow-up diagnostic tests, like amniocentesis or CVS, for confirmation.

Limitations of the NIPT Test

While the NIPT test is a powerful screening tool, it does have some limitations. NIPT cannot detect all chromosomal abnormalities or genetic conditions. It primarily focuses on trisomies 21, 18, and 13 and sex chromosome disorders. NIPT also cannot provide information about other aspects of the baby's health, such as structural birth defects or neural tube defects. In rare cases, NIPT may give a false-positive or false-negative result, which is why confirmatory diagnostic testing is crucial.

Are There Any Risks to the NIPT Test?

There are no known risks associated with the NIPT test for either the mother or the baby. As the test only involves a standard blood draw, there is no risk of miscarriage or harm to the foetus.

Is the NIPT Test Worth It?

For many expectant parents, the NIPT test provides valuable peace of mind and information about their baby's health. It is a highly accurate and safe way to screen for common chromosomal disorders early in pregnancy without the risks associated with invasive diagnostic tests. However, the decision to have the NIPT test is a personal one that should be made in consultation with your doctor. Factors to consider include your individual risk factors, preferences for prenatal testing, and the potential impact of the results on your pregnancy management.

Final Thoughts: Empowering Parents with Early Screening

The NIPT test has revolutionised prenatal care, providing expectant parents with a safe and reliable way to screen for chromosomal abnormalities early in pregnancy. By offering accurate and non-invasive testing, NIPT empowers families to make informed decisions and prepare for their baby's arrival. At Metropolis Healthcare, we understand the importance of prenatal screening and offer NIPT as part of our comprehensive diagnostic services. Our team of experts is dedicated to providing expectant parents with the information and support they need to navigate their pregnancy journey with confidence.

If you’re expecting and want early insights into your baby’s health, you can book an NIPT test today at Metropolis Healthcare and check NIPT test price.
 

Also Read: Nuchal Translucency: What It Is and Why It Matters

FAQs

Is the NIPT test 100% accurate?

No, while the NIPT test is highly accurate, it is not 100% accurate. False-positive and false-negative results can occur, which is why abnormal results should always be confirmed with diagnostic testing.

At what week of pregnancy can I take the NIPT test?

The NIPT test can be performed as early as the 10th week of pregnancy, as there needs to be sufficient foetal DNA in the mother's bloodstream for accurate analysis.

Is NIPT a diagnostic or screening test?

The NIPT test is a screening test, not a diagnostic test. It can indicate an increased or decreased risk for certain chromosomal conditions but cannot definitively diagnose them.

Can NIPT tell the baby's gender?

Yes, the NIPT test can determine the baby's sex with high accuracy by analysing the presence or absence of Y chromosome DNA in the mother's blood.

What should I do if my NIPT test is positive?

If your NIPT test result is positive or high-risk, your doctor will recommend a diagnostic test, such as CVS or amniocentesis, to confirm the result and discuss the implications and options for your pregnancy.

How long does it take to get NIPT test results?

NIPT test results are usually available within a week or two after the blood sample is taken, but this may vary depending on the laboratory and the specific test performed.

Is NIPT recommended for all pregnant women?

While the NIPT test is available to all pregnant women, it is particularly recommended for those at higher risk of chromosomal abnormalities, such as women over 35 or those with a personal or family history of genetic disorders.

Does the NIPT test show the sex of the foetus?

Yes, the NIPT test can accurately determine the sex of the foetus by analysing the presence or absence of Y chromosome DNA in the mother's blood sample.

Can NIPT testing be done for Down syndrome?

Yes, the NIPT test is highly accurate in screening for Down syndrome (trisomy 21), with a detection rate of over 99% and a low false-positive rate.

Can NIPT be done at 14 weeks?

Yes, the NIPT test can be performed at 14 weeks of pregnancy or later, as long as there is sufficient foetal DNA in the mother's bloodstream for accurate analysis.