NIPT Test (Noninvasive Prenatal Testing)- What To Expect

Non-invasive prenatal testing (NIPT) is a screening method that’s used during pregnancy to identify the chances of chromosomal abnormalities in the fetus. This procedure provides the expectant parents with important information about the baby’s genetic health and doesn’t carry risks such as those we see with invasive procedures (e.g., amniocentesis).

In this article, we will explain what the NIPT test involves, which conditions it screens for, how results are interpreted, and what to expect during the process. We will also answer some common questions, including test accuracy and costs.

For professional testing, you can book an NIPT Test in the UK with Ultrasound Plus.

What Is a NIPT Test?

The NIPT test analyses cell-free fetal DNA (cfDNA), which can be found in the maternal bloodstream. These fragments come from the placenta, and they are representative of the baby’s genome. The test is generally performed after 10 weeks of pregnancy.

The key difference between NIPT and other diagnostic procedures, such as chorionic villus sampling (CVS) or amniocentesis, is that the former is non-invasive. All that’s required to perform NIPT is to withdraw a blood sample from the mother.

What Conditions Does NIPT Screen For?

NIPT is mainly used to assess the risk of these trisomies:

Some NIPT panels also detect sex chromosome abnormalities (e.g., Turner syndrome, Klinefelter syndrome), microdeletions, and fetal gender (optional).

What To Expect During the NIPT Procedure?

Here’s a guide on what to expect:

Understanding NIPT Test Results and Normal Range

NIPT results are usually reported as low risk or high risk for each condition tested. The interpretation is based on the statistical odds that the fetus has a certain chromosome abnormality.

Here is an example of the result format:

Here’s a breakdown of the expected results:

• Low risk means it is unlikely that your baby has the condition.
• High risk means there is a greater chance. However, it does not confirm it. That’s why your provider may request additional diagnostic testing.

Some reports include z-scores or fetal fraction percentages, especially when we assess test quality. A fetal fraction below 4% may require repeat testing.

Accuracy and Limitations

NIPT is extremely accurate for Down syndrome. In fact, it has a sensitivity of over 99% and a very low false-positive rate. For Edwards’ and Patau’s syndromes, the sensitivity ranges from 95–98%. However, accuracy may be slightly lower than for Trisomy 21.

With that said, NIPT remains a screening test, and rare false results can occur due to:

• Confined placental mosaicism.
• Vanishing twin syndrome.
• Maternal chromosome conditions.
• Low fetal fraction in early gestation.

Benefits of NIPT

The benefits of NIPT include:

• No risk to the fetus.
• High accuracy for common trisomies.
• Earlier reassurance (from 10 weeks).
• Can identify fetal sex if the parents desire that.
• Fewer false positives compared to first-trimester combined screening.

Who Should Consider NIPT?

NIPT may be especially useful for:

• Pregnant women above the age of 35. 
• Families with a history of chromosomal conditions.
• Individuals who received abnormal ultrasound findings.
• Anyone who wants early reassurance with high sensitivity.

FAQ’s 

The NIPT test has transformed prenatal care since it provides highly accurate and risk-free screening for the most common chromosomal conditions. It’s quick, safe, and can give parents early insights into their baby’s health and even gender when the latter is requested. 

Regardless of whether you want a basic trisomy screen or a full genomic panel, it’s indispensable to choose a reputable provider. For professional service and fast turnaround.