What is the NIPT test?
NIPT stands for noninvasive prenatal testing. It’s a screening test offered during pregnancy to see if the fetus is at risk for having a chromosomal disorder like Down syndrome (trisomy 21), trisomy 18 (Edwards syndrome) and trisomy 13 (Patau syndrome). The test can also determine the sex of the fetus. It’s done by taking a sample of your blood, which also contains fragments of DNA from the fetus. DNA makes up a person’s genes and chromosomes, and gives healthcare providers a glimpse into the fetus’s genetic makeup. The blood sample is sent to a lab and analyzed for specific congenital disorders. NIPT can’t screen for all chromosomal or genetic conditions.
The NIPT test is also called cell-free DNA (cfDNA) screening or noninvasive prenatal screening (NIPS). It’s important to remember that a screening test estimates the likelihood of the fetus having a particular condition. It doesn’t diagnose a condition. NIPT testing is optional. Your healthcare provider will provide information about prenatal genetic testing and help you make an informed choice about your options.
What does the NIPT test screen for?
NIPT doesn’t test for all chromosomal conditions or birth disorders. Most NIPT tests screen for:
- Down syndrome (trisomy 21).
- Trisomy 18.
- Trisomy 13.
- Disorders affecting sex chromosomes (X and Y).
An extra chromosome causes Down syndrome, trisomy 18 and trisomy 13. Screening for sex chromosomes can help predict the sex of the fetus and can also screen for differences in the usual number of sex chromosomes. The most common sex chromosome conditions are Turner syndrome, Klinefelter syndrome, Triple X syndrome and XYY syndrome. Not all NIPT panels evaluate for the same conditions. It’s important to talk to your healthcare provider about what your NIPT is screening for.
Why is noninvasive prenatal testing done?
Noninvasive prenatal testing helps determine the fetus’s chances of being born with certain chromosomal disorders. Healthcare providers may recommend it if you:
- Have a child with a chromosomal abnormality.
- Have had an ultrasound that shows that the fetus may have an abnormality.
- Have had an earlier screening test that suggests a potential problem.
The American College of Obstetricians and Gynecologists (ACOG) used only to recommend NIPT for pregnant people considered high risk. However, it’s now recommended that providers offer NIPT to all pregnant people, regardless of risk.
Based on the results of the NIPT test, your obstetrician may recommend diagnostic tests. Diagnostic tests give a definitive answer about whether the fetus has a specific condition.
When should the NIPT test be done in pregnancy?
NIPT testing can be done as early as 10 weeks of pregnancy through delivery. There’s typically not enough fetal DNA in a pregnant person’s blood before 10 weeks of pregnancy.
How accurate are NIPT tests?
The accuracy of the test varies by the condition that it’s checking for. Other factors — like being pregnant with multiples, being a surrogate or having obesity — can affect NIPT results.
NIPT is about 99% accurate in detecting Down syndrome. The test is slightly less accurate for detecting trisomy 18 and 13. Overall, NIPT tests produce fewer false positives than other prenatal screenings like the quad screen.
Does the NIPT test show the sex of the fetus?
Yes, NIPT can predict the sex of the fetus.
Is it necessary to get the NIPT test during pregnancy?
No, it’s not necessary. It’s a personal choice, and it’s normal to have questions. Your healthcare provider will discuss all your prenatal screening options, including NIPT. Many factors may go into your decision to have NIPT and prenatal genetic testing in general. If you’re having a difficult time or wish to discuss the screenings in more detail, a genetic counselor can help you understand the prenatal testing options and what may be a good fit for you.
How do doctors perform a NIPT test?
During this test, your provider takes a sample of your blood to look for abnormalities in the fetus’s DNA. Your DNA is inside all of your cells. Your cells are constantly dividing and creating new cells. When cells break down, tiny DNA fragments are released into your bloodstream. You have a small amount of the fetus’s DNA circulating in your bloodstream during pregnancy. The NIPT looks at these fragments of fetal DNA in your blood — known as cell-free DNA or cfDNA.
Your provider obtains a blood sample through a vein in your arm. They send this sample to a lab to analyze it for specific conditions.
It’s important to note that it takes about 10 weeks for enough fetal DNA to circulate in your blood. That’s why the screening isn’t performed until 10 weeks into the pregnancy.
Are there any risks to the NIPT test?
NIPT tests are safe, and there’s no risk to the fetus. It requires drawing blood from the pregnant person only.
Results and Follow-Up
When should I get my test results?
Results from NIPT tests can sometimes take up to two weeks, although results are often available sooner. Your healthcare provider will receive your test results first, then share the results with you.
What do the results of the NIPT test mean?
NIPT is a screening test, which means that it won’t give a yes or no answer about whether or not a fetus has a condition. The result will show if there’s an increased or decreased risk for a fetus to have the condition being screened. Your test results may sometimes be hard to interpret, so ask your healthcare provider for help if you’re unsure.
Most labs give separate results for each condition they’re screening for. For example, you may get a positive or high-risk result for trisomy 13 but a negative or low-risk result for Down syndrome.
There’s also the possibility that no test results are given due to insufficient fetal DNA in your blood or difficulty identifying fetal DNA. In this case, you can repeat the NIPT test and hope for a result the second time. Your healthcare provider can best guide you in these situations.
If noninvasive prenatal testing indicates that the fetus is at risk for a chromosomal disorder, your provider may recommend diagnostic testing. These tests diagnose conditions and give a yes or no answer:
- Amniocentesis: Amniocentesis is a procedure in which a small amount of amniotic fluid is taken from your uterus. This test can be performed after 15 weeks of pregnancy.
- Chorionic villus sampling (CVS): During chorionic villus sampling test, cells are taken from the placenta. The cell sample is sent to a lab. This test can be performed between 10 and 13 weeks of pregnancy.
It’s important to discuss the results of your NIPT with your provider so you have all the information you need to determine the next steps.
Can NIPT testing be wrong for Down syndrome?
NIPT is a screening test and, therefore, isn’t perfect. It’s important that you talk to your healthcare provider about your results and options to get more information.
Is the NIPT test worth it?
Getting a noninvasive pregnancy screening or other prenatal genetic test is up to you. Your healthcare provider can answer any questions you have, but ultimately you have to decide how a genetic or chromosomal disorder affects you and your family based on your situation.
The following questions might be helpful to you as you make your decision:
- How will I feel about a positive screening result?
- Would I consider diagnostic tests like amniocentesis or CVS?
- Would I do something different knowing the fetus has a genetic condition or an increased risk for a genetic condition?
- Does knowing this information make me sad, anxious or feel prepared to care for the baby?
- Would knowing this information help my provider(s) take better care of the baby?
How much does the NIPT test cost?
NIPT testing costs vary. Most health insurances cover most (if not all) of the cost. Many cover at least a portion. Check with your insurance provider before testing to be sure. If you don’t have insurance or your insurance doesn’t cover NIPT tests, you can pay for the test.
Can NIPT be done at 14 weeks?
Yes, NIPT can be done anytime after 10 weeks of pregnancy.
What questions should I ask my doctor about the NIPT test?
Noninvasive pregnancy screening tests are a personal choice. You may have questions about what your results mean or if you should even have the NIPT test. Don’t be afraid to ask questions. Remember, only you and your family can decide what’s best for you.
Some common questions to ask your healthcare provider are:
- Would you get the NIPT test if you were me?
- If my screening test is positive, what are the next steps?
- Is a genetic counselor available to talk to me about my options?
- What are the chances of false positives?
A note from Cleveland Clinic
The NIPT test is a highly reliable prenatal screening tool that assesses the risk of chromosomal disorders in a fetus. This test can also provide information about the sex of the fetus. NIPT testing doesn’t diagnose conditions — it only suggests a fetus is more likely to have a particular condition. Diagnostic testing may be recommended after you get NIPT test results. Prenatal tests like NIPT are optional, and getting the test is entirely up to you. Talk to your healthcare provider or a genetic counselor about your concerns. Be sure to understand what the test screens for and what the results mean so you make an informed decision.
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