Attention pregnant women: FDA warns that prenatal screening tests may have false results

The U.S. Food and Drug Administration is warning that common blood tests used to screen pregnant women for signs of genetic abnormalities in their pre-born babies run the risk of giving false results.

On Tuesday, the FDA put out a safety communication advising expecting parents that genetic non-invasive prenatal screening tests, sometimes called non-invasive prenatal testing or tests, or NIPTs, have not been authorized or approved by the agency. The agency said that women have chosen to kill their unborn children based on the results of these tests, which run the risk of false-positives.

NIPTs are blood tests done to screen an unborn child for genetic conditions that could result in that child being born with serious health problems. The FDA warns that the accuracy and performance of these widely used tests has not been evaluated by regulators and that false results could lead parents to believe their unborn babies have a genetic disorder when they do not.

"The FDA is aware of reports that patients and health care providers have made critical health care decisions based on results from these screening tests alone and without additional confirmatory testing," the agency said. "Specifically, pregnant people have ended pregnancies based only on the results of NIPS tests."

The FDA strongly emphasized that there is a distinction between screening, which evaluates the risk of a child having certain genetic abnormalities, and diagnosis, which confirms or rules out disease.

"Without confirming the results with a diagnostic test, there is no way to know whether the fetus actually had the genetic abnormality reported by the screening test," the FDA said, adding that there have been cases where a follow-up diagnostic test after a positive screening test found that the unborn child was actually healthy.

Prenatal screening tests available today are categorized as laboratory developed tests, which are not subject to review by the FDA. The New York Times reported in January that more than a third of pregnant women in America have sought the services of NIPT providers. The report revealed that as many as 80% of the screening results for rare genetic conditions were false positives, which led some women to consider seeking abortions when they had healthy babies.

The FDA said that companies offering prenatal screening market the tests as "reliable" and "highly accurate" so that expecting parents can have "peace of mind." But these claims are not based in "sound science," Dr. Jeff Shuren, director of the FDA's Center for Devices and Radiological Health, said in a statement.

“Without proper understanding of how these tests should be used, people may make inappropriate health care decisions regarding their pregnancy. We strongly urge patients to discuss the benefits and risks of these tests with a genetic counselor or other health care provider prior to making decisions based on the results of these tests,” he said.

Congress is working with the FDA on bipartisan legislation that would give the agency regulatory power over the safety and efficacy of genetic testing and also over how the tests are marketed to patients.