Non Invasive Prenatal Test
Pieces of the baby’s DNA circulate in the mother’s bloodstream. Noninvasive prenatal testing (NIPT) involves a simple blood screening that analyzes that DNA (cell-free DNA or cfDNA) to identify a baby’s risk for a number of genetic disorders, including Down syndrome.
NIPT is a prenatal screening, which looks at DNA from the baby’s placenta in a sample of the mother’s blood to identify whether there is an increased risk of giving birth to a child with a genetic disorder. A screening like NIPT cannot, however, determine for sure whether your baby actually has a chromosomal disorder, only the probability of having that condition. However, it is highly accurate — 97 to 99 percent accuracy for three of the most common conditions.
The results of a NIPT screening can help you and your doctor decides the next steps, including whether to have a diagnostic test like chorionic villus sampling (CVS) or amniocentesis (“amnio”). These genetic tests analyze a baby’s own genetic material, collected from the amniotic fluid or placenta, to tell with 100 percent certainty whether a baby has a chromosome abnormality. Since a NIPT involves only a quick blood draw with a needle and syringe, it’s safe for the mother and the baby. The sample is then sent to a lab, where a technician will look at the cfDNA in the blood for signs of abnormalities.
Once the results of the NIPT are back, the doctor will likely pair them with the results of the first-trimester or nuchal translucency screening to determine whether further testing is needed. If it’s positive, the doctor may recommend following up with amniocentesis or CVS to confirm the result and check for other problems NIPTs can’t detect.