It has stated, “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,” in a press release.
A recent media coverage of a Hastings Center Report has found out that the marketing around these NIPTs often included misleaded and false information. The test may result in a false positive or a false negative. This leaded parents to terminate a normal pregnancy.
has issued a similar report.
The FDA took this into account and has issued a statement that advertising claims on the tests, such as that they are “reliable” and “highly accurate,” may not be supported with “sound scientific evidence.”
The likelihood of a result being a false positive. For instance, with very rare conditions caused by a small missing piece of a chromosome (microdeletion, a positive result) is more likely to be false than it is that the fetus has a disease.
The agency stated, “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 also said that 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 Truth About NIPT
NIPT is a screening test and not a diagnostic test and may provide a false positive or false negative result. Patients and their healthcare providers should understand NIPT results may not always be conclusive and that in most cases, the final diagnosis of any developmental condition will be made after the birth of the child.
A false positive result means that a common disorder is detected, but the fetus actually has no such condition. It is called “false” because the results are wrong. A false positive result may lead to invasive testing and even surgery, which in turn will lead to anxiety and unnecessary cost to the patient and family. However, a false test result of microdeletion syndrome is less likely than a true one as the chance of both parents carrying the mutations on their respective chromosomes are slim.
The agency has 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,” as told by Jeff Shuren, MD, JD, director of the FDA’s Center for Devices and Radiological Health. “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 MedPage Today 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.”
Source: Medindia
