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Prenatal Blood Test Info Often Misleads, Endangering Normal Pregnancies

— Report blasts misleading language around non-invasive prenatal blood tests

MedpageToday
A photo of the Verifi prenatal test packaging.

Misleading language in marketing materials for non-invasive prenatal blood tests (NIPT) brought the industry into the crosshairs of a Hastings Center , particularly for-profit companies.

The report said many of the promotional brochures had the potential to confuse would-be parents about what results actually show and could lead them to terminate a normal pregnancy.

"Poor-quality information poses the potential for harm from increased shock, distress, and confusion upon receipt of a high-chance result and may even lead to termination of an unaffected fetus if the possibility of a false-positive result is not clearly communicated," the report said.

For example, the Hastings researchers said many of the brochures failed to make clear that these are only screening tests indicating a chance the baby will have a certain chromosomal sequence, such as Down or Edwards syndrome.

"The misrepresentation of NIPT as a diagnostic test in 52% of the brochures is particularly noteworthy, as patients who do not understand that follow-up diagnostic testing is required to confirm a positive NIPT result may make decisions about their pregnancy based solely on the results of the NIPT," their report said.

The research was conducted by medical sociologist Kelly Holloway, PhD, and colleagues at the Institute of Health Policy, Management and Evaluation at the University of Toronto, based on test company brochures accessed in 2019.

Although there were some 57 entities offering NIPT test brands, the Hastings researchers to English-language testing brochures distributed by 27 for-profit NIPT companies and five non-profit companies through 2019.

It's unclear whether the situation has improved since that time, senior author Fiona Miller, PhD, told 鶹ý.

But if history is any guide, change might be slow. The U.K.'s Nuffield Council on Bioethics tried to raise similar issues in 2017 but tracked " through 2019.

When Miller's group looked at the patient information in 2019, NIPT companies failed to meet most of the 15 set as benchmarks established by the Nuffield Council on Bioethics, and for-profit entities were "less compliant overall than non-profit entities."

None of the companies were compliant with all of the council's criteria or even the 11 designated by the council as "essential." Only four met 10 or more criteria. Additionally, many of the companies consistently failed to offer evidence in their brochures to support claims about their test's accuracy.

"These findings lend credibility to the [Nuffield] council's concern about how commercial imperatives could exacerbate problems of misrepresentation and inaccuracy in marketing materials," the report said.

A New York Times of NIPTs earlier this year found that they were usually wrong about anything beyond Down syndrome, with an 85% false positive rate for the five most common microdeletion tests.

Usually performed between the ninth and 21st week of pregnancy, NIPTs commonly use a blood sample to test for Down, Edwards, or Patau syndrome, although many other single nucleotide polymorphisms or microdeletions may be included in the panel. The cost is between $500 to $800, Holloway said in an email to 鶹ý. She pointed to a website showing detection rates between 88% and 99% or better for those three syndromes, but chances vary that a test will be a false positive.

At least one class action lawsuit has been filed against , over false positive NIPT results. One from 2014 documented cases where normal pregnancies had been terminated following false positive screens, and the New York Times investigation cited more recent cases as well.

A theme throughout Miller and colleagues' evaluation was that despite the proliferation of the prenatal test market since the technology began in China in 2010, there is "a gaping regulatory hole." No independent regulatory agencies govern market access, such as the FDA. Therefore, there is no review of language used in marketing materials, especially those targeting women, the report said. That responsibility falls to the test marketers themselves.

In the absence of any such review, many brochures say that undergoing these tests can bring "reassurance" or "peace of mind," when according to the authors, they should make it clear that in the case of a positive result, other very difficult decisions must be made, such as whether to undergo more invasive diagnostic testing or whether to continue with the pregnancy.

"Brochures from for-profit companies were particularly deficient in clarifying that the test could lead to such decisions, with only 32% in compliance with the council's guidelines; nonprofits' brochures were more consistent at 60%," the authors wrote.

A big concern expressed in the report was that the requirement for the tests to be obtained through a clinician doesn't guarantee skills in interpretation.

Many clinicians, including obstetrician-gynecologists, maternal-fetal medicine specialists and nurses, "vary in their understanding of NIPT -- and their ability to communicate about it -- with many unable to clearly explain the strengths and limitations of the technology or what it means for patient decision-making," according to the report.

Nevertheless, 57% of the brochures from the for-profit companies, but none from the non-profit companies, said the patient's physician would be able to explain the test.

Asked what level of clinical training the patient should seek when considering whether to get a non-invasive prenatal test, Holloway said in an email that clinical medical education should include training about the potential for the industry selling these tests to use biased language.

Another major issue the Hastings researchers discovered was that the companies "consistently failed to offer evidence to support their claims" about test performance using "recent, peer-reviewed, high quality clinical data" that they could provide if asked.

Many used language that implied their test was approved by an independent organization or authority, such as the College of American Pathologists. "This could impart the impression that the test itself has been externally validated by such regulations and entities, even though that is not their function," the authors wrote.

"In the context of a commercially driven market with a weak regulatory regime, our findings point to important health policy questions about how NIPT is disseminated and who is responsible for ensuring public safety," the authors concluded.

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    Cheryl Clark has been a medical & science journalist for more than three decades.