Noninvasive Prenatal Testing for Rare Diseases Is Wrong More Times Than Right: Report

Noninvasive prenatal tests have an alarmingly high rate of false positives when screening for extremely rare diseases, according to a new report by The New York Times. On average, they are reportedly incorrect 85 percent of the time. The technology, referred to as NIPT, takes blood drawn from the mother during the first trimester to screen the fetus’ DNA for any potential of a developmental issue. While the test has a very high success rate of detecting common disorders, such as Down syndrome and Edwards syndrome, results are highly inaccurate when it comes to rare conditions, experts told the Times. The tests are often wrong when attempting to identity conditions that have microdeletions, where portions of the chromosome are missing. In America, NIPTs are fairly common, with about a third of women voluntarily opting to undergo the testing. False results can send expecting parents into an unnecessary tailspin, as follow-up testing is encouraged and often can cost the patient thousands of dollars. In addition to the tests being risky, running a chance of miscarriage, they are also carried out later in the pregnancy, which depending on where the patient lives, could be past the point of when abortions are legal in that state.