Prenatal testing has come a long way in the past 100 years. Women are now able to have ultrasounds and other forms of testing that allow them to know exactly how many babies they?re having, what the sex of the baby is, and other potential health risks to the fetus. However, it?s common to hear stories about women who gave birth to twins despite an ultrasound showing a single baby, or about women who gave birth to a boy after being told she was having a girl. These surprises are reminders that there are instances in which modern prenatal technologies can fail to accurately capture a pregnancy. So, what does this mean for relatively new developments in non-invasive prenatal testing? How reliable are they?
What is Non-Invasive Prenatal Testing
Non-invasive prenatal testing (NIPT) is a simple blood test that can be performed as early as nine weeks into a pregnancy. The results of this test give the parents valuable information about the risks that their child could be born with a genetic disorder. These tests use DNA from the fetus found circulating in the mother?s blood to check for markers indicating a variety of genetic conditions like cystic fibrosis, Down syndrome, and open neural tube defects.
How Accurate is NIPT?
This form of testing is able to provide a high degree of accuracy– usually around 85% depending on the circumstances of the test (timing, etc.). Researchers have also learned that NIPT can actually be more accurate than other forms of prenatal testing for Down syndrome.
Many doctors are now recommending this kind of testing to their patients during initial prenatal visits because of its demonstrated success at detecting risks. However, one very important thing to note about non-invasive prenatal testing is that it is not definitive proof that a child will be born with a particular genetic condition. Other more-invasive forms of diagnostic testing are necessary to know for certain whether a baby has a particular genetic disorder, but these can also come with an increased risk to the unborn child.
What if My Results Are Positive, Negative, or Inconclusive?
Receiving a positive result from a non-invasive prenatal screening test can indicate that your child is at risk of being born with a genetic disorder. Your doctor will receive the results and share them with you. If you were to receive a positive or inconclusive result from an NIPT, they will likely refer you to a genetic counselor to discuss additional testing options and further diagnostic testing. A negative result from an NIPT likely means that your child is at low risk of being born with a genetic condition, and that you can continue with your pregnancy as indicated by your doctor.
Who Can I Speak to For More Information?
If you have any questions about NIPT, your results, or other kinds of DNA testing, it?s best to speak with a genetic counselor. They are able to provide guidance and support for anyone considering NIPT and those who have already begun the process.