The clinical specificity for any trisomy was 99.9% (95% CI 99.8%–99.9%). Compared with traditional prenatal screening, NIPT was more accurate in detecting trisomies 21, 18, and 13, and decreased the need for diagnostic testing.

To diagnose triple X syndrome, a blood sample is checked for the presence of the extra X chromosome. Before birth, the condition can be found through a chromosomal analysis. Testing is done on the fluid surrounding the fetus, tissue from the placenta, or the blood from the mother.

Trisomy X can be accurately diagnosed during pregnancy by chorionic villus sampling (CVS) or amniocentesis. A prenatal screening test called non-invasive prenatal testing (NIPT) or cell-free DNA testing can also check for trisomy X.

There is no cure for triple X syndrome. A girl born with the disorder will always have a third X chromosome. Treatment involves providing support for girls and women to manage their symptoms.

The chances of a sex determination via NIPT being wrong is around 1 percent when the test is conducted after week 10 of your pregnancy or later, Schaffir says.

How accurate is the NIPT? According to this 2016 study , NIPT has a very high sensitivity (true positive rate) and specificity (true negative rate) for Down syndrome. For other conditions such as Edwards and Patau syndrome, the sensitivity is slightly lower but still strong.

“We certainly see some kids who are less affected than others, but we shy away from terms like ‘low-functioning’ and ‘high-functioning,’” Pipan explains. Some children with Down syndrome have a hard time learning to walk, and others have no problem running and jumping and riding a bike.

Simply put, the answer is no. The condition of Down syndrome has not been described in dogs. Three explanations are possible: These types of chromosomal abnormalities typically lead to early death in dogs.