The FDA warned that non-invasive prenatal tests (NIPT) are screening tests -- not diagnostic tests -- and patients and healthcare providers may make inappropriate healthcare decisions based on their results.
The agency said it's aware of reports that people have made such decisions using the results of these tests without additional confirmatory testing.
"Pregnant people have ended pregnancies based on the results of genetic prenatal screening alone, without understanding the limitations of the screening test and that the fetus may not have the genetic abnormality identified by the screening tests," the agency .
FDA's warning follows recent media coverage of a Hastings Center report that found the marketing around the tests often included misleading information, which could lead parents to terminate a normal pregnancy. had also reported on rates of false positives with the tests earlier this year. The agency said in its statement that it is "concerned" that advertising claims on the tests, such as that they are "reliable" and "highly accurate," may not be supported with "sound scientific evidence."
The issue centers around the likelihood of a result being a false positive. For instance, with very rare conditions caused by a microdeletion -- a small missing piece of a chromosome -- a positive result is more likely to be false than it is that the fetus has the disease.
"In other cases," , "a positive screening result may accurately detect a chromosomal abnormality, but that abnormality is present in the placenta and not in the fetus, which may be healthy."
FDA said additional testing of a genetic screening result, such as amniocentesis or chorionic villous sampling, may be needed to confirm whether the fetus indeed has the genetic disorder.
The agency also warned that none of the NIPT tests are authorized or approved by the FDA. Rather, they're all classified as laboratory developed tests (LDTs), which means their accuracy and performance aren't evaluated by FDA. The agency has had a general policy of "enforcement discretion" for most LDTs, which means it doesn't generally enforce applicable regulatory requirements for these tests.
FDA stated in its press release that it is "continuing to work with Congress on legislation to establish a modern regulatory framework for all tests, including LDTs."
"While genetic non-invasive prenatal screening tests are widely used today, these tests have not been reviewed by the FDA and may be making claims about their performance and use that are not based on sound science," Jeff Shuren, MD, JD, 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."
Josephine Johnston, director of research at The Hastings Center, told 鶹ý that the FDA's safety communication "is a way of doing a little bit of regulation of an area they don't regulate. ... This is the only thing they can do."
She noted that FDA's review of its LDT regulatory policy has been ongoing for several years. "Tests are falling under this exemption they were never intended for, but it's never changed," she said. "There are probably strong and forceful arguments on both sides of the issue."