Since the advent of prenatal testing in the mid-1950s, more and more mothers have opted for genetic testing for early detection of chromosomal irregularities in their babies. However, some of these tests are invasive, carrying with them a slight risk of miscarriage or other complications. Non-Invasive Prenatal Testing, or NIPT, offers a genetic testing solution without the risks of an invasive procedure.
What Is Non-Invasive Prenatal Testing?
During pregnancy, blood from the placenta circulates along with your blood, allowing a small amount of your baby’s DNA to be present in your bloodstream. NIPT can test this DNA to determine if your baby is at risk for certain, common genetic conditions. While NIPT cannot tell you for sure that your baby has a genetic condition, it is very accurate and can help you and your doctor decide if further testing is necessary.
How Is NIPT Performed?
As early as 9 weeks’ gestation, a simple blood draw from your arm can provide enough of your baby’s DNA for testing. The sample is sent to a lab, where it is tested for a number of chromosomal abnormalities including trisomy 21 (Down syndrome), trisomy 18 (Edwards’ syndrome) and abnormal numbers of X or Y chromosomes. At this time, NIPT will also be able to determine your baby’s sex.
NIPT has a turnaround time of approximately 5 days from receipt of your sample in the lab, which means your doctor will have your results fairly quickly. If you’ve previously had nuchal testing, your doctor will discuss both sets of results with you at this time; any “increased risk” results may indicate the presence of a chromosomal abnormality. In this case, your doctor may recommend further diagnostic tests like amniocentesis and chorionic villus sampling (CVS) for confirmation.
What Are the Benefits of NIPT?
Since NIPT does not access the placenta, there is no risk of miscarriage or other complications for you or your baby. In fact, NIPT has the potential to reduce risk from unnecessary, invasive procedures by providing low-risk mothers and their healthcare providers the opportunity for well-informed discussion of such procedures before choosing to move ahead with them. As mentioned, the turnaround time is relatively speedy and doctors can perform the test as early as 9 weeks, allowing them to review results along with other early-pregnancy screens.
NIPT is very sensitive, indicating risk for abnormalities such as Down syndrome and Edwards’ syndrome more often than other tests. As with any very sensitive test, some false positives may occur, but the risk of this is potentially lower than other popular early-pregnancy tests.
Why Should Doctors Recommend NIPT?
This year, more mothers than ever – 15%, according to Evidence Based Birth – are of advanced maternal age, 35 or older at birth. Since instances of Down syndrome and other chromosomal abnormalities increase with age, doctors should recommend the NIPT to any mothers over 30, though insurance typically covers testing for mothers 35 or over. However, the testing is available for any mother regardless of age.
No matter your age or risk factors, your doctor should discuss all potential testing with you to determine which tests are right for your pregnancy. NIPT can help you and your doctor decide which next steps are available and help prepare you for any potential outcomes.
SOURCES:
https://www.whattoexpect.com/pregnancy/pregnancy-health/noninvasive-prenatal-testing/
https://www.webmd.com/baby/non-invasive-prenatal-diagnosis-nipd
https://evidencebasedbirth.com/advanced-maternal-age/
https://www.thehastingscenter.org/prenatal/evolution-prenatal-testing/