Most expectant moms are faced with a barrage of tests throughout pregnancy to monitor their own health and the health of their baby. This includes prenatal screening, such as non-invasive prenatal testing (NIPT), which has advanced rapidly over the last few years. Now, expectant mothers can take a simple blood test – as early as 10 weeks into the pregnancy, and as late as full-term – to find out if their fetus has certain chromosomal abnormalities such as Down syndrome. This can cause increased anxiety due to the complexities of the process and anticipating the results
As a prenatal genetic counselor, I help women and families navigate through the testing process including the critical – but often skipped – step of pre-test counseling. For all moms-to-be undergoing prenatal screening, my number one piece of advice is: be your own advocate.
About prenatal screening
NIPT, also known as non-invasive prenatal screening (NIPS), can empower women with information about their baby. Tests like NIPT screen for Down syndrome and trisomy 18 with approximately 99 percent accuracy. In addition, NIPT can screen for trisomy 13, and some sex chromosome abnormalities such as Turner syndrome and Klinefelter syndrome , but there is more limited research on detection rates for these abnormalities.
As with any medical test, however, there are limitations for physicians and patients to consider. NIPT is a screening test and does not replace diagnostic tests such as chorionic villus sampling (CVS) or amniocentesis. Although the detection rates for NIPT are quite high, it will not detect all chromosome abnormalities. Women with an abnormal NIPT result should be offered CVS or amniocentesis to confirm the presence of the chromosome abnormality due to the potential for false positive results.
How to be your own advocate
All pregnant women should be counseled about prenatal screening and testing for chromosome abnormalities because the process is complex, and NIPT is only one of several options. Each of these options has its own set of benefits and limitations that should be considered. Because NIPT accurately indicates whether a fetus has certain abnormalities – and is a new technology that will continue to develop – women should receive counseling from a qualified health care provider such as a certified genetic counselor prior to taking the test and when they receive the results. It's also important to understand exactly what the test is and what the results may determine.
Before undergoing any prenatal screening or genetic testing, be your own advocate and seek clarification on the type of test you are receiving. Ask your physician questions such as:
- What type of test is it – NIPT/NIPS, first trimester screen or quad screen?
- What could the results tell me about my baby?
- If there's an abnormal result, what's the next step?
- Can you refer me to a genetic counselor before testing?
For many couples, obtaining the most reliable information about the health of their baby without putting the pregnancy at risk is an ideal situation. NIPT is an option that moves us closer to that goal. The National Society of Genetic Counselors is working closely with obstetricians and other health care professionals who care for pregnant women to ensure that patients understand NIPT and other prenatal tests, and are able to receive genetic counseling. You can connect with a genetic counselor in your area using NSGC's “ Find a Genetic Counselor ” tool.
Jennifer Hoskovec , MS, CGC, is president of the National Society of Genetic Counselors, and the Director of Prenatal Genetic Counseling Services at the University of Texas Medical School at Houston.