Non-invasive prenatal testing (NIPT) is a simple blood test that analyses pieces of your baby’s DNA during pregnancy and is completely safe for you and your baby.
The blood test looks at tiny pieces of cell-free DNA (cfDNA) from the placenta that have made their way into your blood. It is used to identify if your baby has a chance of being affected by a chromosomal abnormality including Down’s Syndrome (trisomy 21), Edwards’ Syndrome (trisomy 18), and Patau’s Syndrome (trisomy 13).
You will only be offered NIPT if the usual screening test, which consists of a blood test and an ultrasound scan at either the 12 week or 20 week scan, suggests that your baby has a higher risk of these conditions. A higher chance result is one that’s between one in two and one in 150.
While the usual screening tests have an 86% detection rate for Down’s Syndrome and 80% detection for Edwards’ and Patau’s Syndromes, NIPT is between 97 and 99% accurate.
To be clear, NIPT still cannot tell you if your baby has these conditions, rather it can tell you the likelihood that your baby has that condition. If your baby does have a high chance of one of these conditions, you and your doctor will discuss the next steps, including perhaps genetic tests that can tell you for sure whether your baby has a chromosomal abnormality.
You might also be offered NIPT if you’re older than 35 or you have a personal history of pregnancy with a chromosomal abnormality. You won’t be offered NIPT if you have chromosomal abnormalities, are carrying multiple babies greater than twins, have cancer, have an organ transplant, or have received stem cell therapy or immunotherapy within the last year.
Ultimately, whether to have NIPT is your choice. If you have any questions about whether NIPT is right for you, speak to your midwife or doctor.