One-half of the problem with the new prenatal tests for Down syndrome

Down Syndrome Prenatal Testing CycleAn investigative report calls attention to one-half of the problem with the new non-invasive prenatal screening tests for Down syndrome and other conditions. 

Over a three month period, Beth Daley with the New England Center for Investigative Reporting looked into how the NIPS labs were marketing their tests, their relative accuracy, and the impact the tests have had on moms receiving false positives and false negatives. Her report is disturbing.

Aborting based on a maybe

It leads off with a mom, Stacie Chapman, being told over the phone by her obstetrician that her NIPS result was positive for Edwards syndrome, also known as Trisomy 18. Chapman, after sharing the news with her husband, scheduled an abortion the very next day. But her OB called her back and encouraged her to have confirmatory diagnostic testing. Chapman did and her NIPS result was shown to be a false positive.

Not all moms get that follow up call, though.

The report further shares how moms are aborting based solely on a NIPS result.

Despite Sequenom’s marketing materials saying “Never maybe” (noted in the NECIR report), that is all that a NIPS result is: they are never truly positive or truly negative. As the report further notes,

Illumina, for example, claims its Verifi screen has “near-diagnostic accuracy,” a term medical experts say has no meaning.

Natera published a study on the accuracy of its testing, based in part on follow up with how pregnancies turned out. It found that 6 percent of those who received a “positive” Panorama test terminated their pregnancies without having diagnostic testing (in a presentation in 2013, the rate was even higher, 17%). Even more concerning, Daley’s report shares how one woman terminated even after receiving a diagnostic test showing her NIPS result was a false-positive. The reason: the mother still trusted the claimed accuracy of the NIPS report.

Highlighting one problem, but contributing to another?

The report was published by the Boston Globe and received rapid distribution on-line among those interested in this topic. It is value-added in raising a brighter spotlight on the overselling being done by the NIPS labs on the accuracy of their tests.

But, I couldn’t read the report as a parent to a daughter with Down syndrome and not also think the report contributes to the problem that underlies all of prenatal testing for genetic conditions. The language used to demonstrate why aborting based on a false positive, or relying on a report that turns out to be a false negative, is troubling.

The article’s word choice is all the more surprising given that it is critical of the language used by the NIPS labs to oversell their tests and the reporter was part of a panel addressing the importance of accurate representations about NIPS at this year’s National Society of Genetic Counselors annual meeting. (See number 203 here).

But, the article describes testing for genetic conditions using these terms:

  • Chapman’s doctor “had bad news” for her.
  • Throughout the tests are testing for a “potential problem,” for “risks … of other chromosomal abnormalities.”
  • False positives are “false alarms.”
  • “Chapman spent the afternoon Googling the horrors of Edwards syndrome” [emphasis mine].
  • Holding her son who does not have Edwards syndrome, Chapman says “[h]e is so perfect” suggesting he would be less so with Edwards syndrome.

The article also shares how a woman with a false negative gave birth to a child with Edwards syndrome. A nurse in the delivery room was overheard wondering, “Didn’t she have that test?” A picture of this mother holding her son is captioned, “Belinda Boydston’s son died days after birth. A screening had been clean.” [emphasis mine.]

This language contributes to the normative effect of prenatal testing: that it is just presumed that what can be tested-for necessarily is a “risk,” a “problem,” a “horror.”

It is with this backdrop of societal bias against disabilities that every expectant mother enters her OB’s office and is then offered testing for these conditions. It is this bias that then informs how mothers process receiving a screen-positive result.

Is it any wonder then that some, fearing these problems, these horrors, these imperfect children, these tests that didn’t come back “clean,” then go ahead and terminate their pregnancies?

The rest of the problem with prenatal genetic testing

The report shares a very telling quote that in part correctly identifies the problem with prenatal genetic testing.

Athena Cherry, professor of pathology at the Standford University School of Medicine, is quoted as saying:

The worry is women are terminating without really knowing if [the initial test result] is true or not.

Indeed, that is the worry. But what “is true or not” should include more than just the initial test result.

“What is true” also needs to encompass whether moms and their partners are adequately counseled on what living a life with the tested-for condition can be like for their children.

Parents of children with Down syndrome do not describe the effects of that condition as “horrors.” To the contrary, they overwhelmingly report loving their children and being proud of their children. While Edwards syndrome does have a profound effect on functionality, that does not strip the child of his or her basic humanity and the opportunity to be profoundly loved. And for the sex aneuploidies that NIPS can test for, some individuals can live into adulthood without ever knowing they have an extra X or Y chromosome because the impact of that extra genetic material can be so minimal in certain cases.

The focus of the article was on women making a “irrevocable choice” based on a maybe of a screening test result. But, the line about Chapman spending the afternoon “Googling the horrors of Edwards syndrome” reveals that no other information was provided with the test result. Chapman wasn’t provided information on the basics of the testing or the conditions it tested for when the testing was offered to her. And, even though the testing company knew she would be receiving a screen-positive result, that testing company didn’t also provide information about the condition itself and the available support services for families raising a child with the tested-for condition. Neither did her OB when she shared the news with Chapman.

Addressing the problem

The article concludes with some doctors recommending that women receive genetic counseling before and after screening testing–indeed the professional guidelines recommend pre- and post-test counseling. But just as that pre- and post-test counseling isn’t being done, neither is the rest of the information that women should be counseled about: accurate written information about the tested for condition and referral to support services so that they can know they are not alone.

The article shares “what is true” about prenatal screening: that most doctors and patients are poorly-educated about it, what its results mean, and how accurate, or inaccurate, screening actually is. But what is also true is that most people are poorly-educated about what it means to have a child with one of the tested-for genetic conditions.

Women are undergoing prenatal genetic testing on the promise of receiving information. Daley’s NECIR report rightfully shows that they need to understand what that information means with how accurate a test is. But women undergoing prenatal genetic testing also need to understand what it means to have a child with the tested for condition, that they are not “horrors” or less-than-perfect and that support services are available to them.

The NECIR will be hosting an on-line chat on Monday, December 15, 2014 from 2 – 3 pm, EST. Ms. Daley and Prof. Cherry will be among the participants. You can leave questions or comments for the chat now and join the chat tomorrow at this link

Comments

  1. Is there any reports of False Positives with Trisomy 21? I am asking due to my current situation that my NIPS came back positive for Downs Syn. and I did not have any follow up diagnosis testing done due to the risks. I still have about 5 months to go yet. But, I am not sure what to believe about all of this?

    • Yes, there are false positives with Trisomy 21–there are false positives and false negatives for every condition tested for by cell free DNA.

      • Any hopes of connecting with someone in my similar situation that has had a positive from NIPS? If there is anybody out there that has ever had a positive and then later found out due to an amnio or birth that it was a false positive please let me know. What do you feel the statistics are in the false positives. My doctor tells me that every positive result they ever received has been true for down syndrome. Ty, for reading this.

        • The graph at this post will show you the likely probability that you are having a child with Down syndrome based on a screen positive test. If you are under 30, it’s less than a 50/50 chance. You can find online support of moms and expectant moms at the babycenter Down syndrome pregnancy board. Another resource is to contact your local Down syndrome support organization. I hope this helps and regret this information was not already provided by your doctor.

          • If you haven’t already, I would also recommend consulting with a prenatal genetic counselor. Best of luck!

  2. You have raised some really important points around the framing of the message in the initial report.

    I’m not following the ethical concern that it would be a worry that women are terminating without knowing whether the rest results are correct though. Is the ethics of that decision dependant on the genetics of the fetus? The implication seems to be that it is unethical to harm based on a wrong diagnosis, but a simple matter of an ethical informed choice to harm based on a correct diagnosis. What have I missed here?

Trackbacks

  1. […] women than ever will be left in the dark when receiving a prenatal test result. Considering that a report was published at the end of the year finding that women are choosing to abort their pregnancies […]

  2. […] 6 – 17% of those who screen positive with cell-free fetal DNA testing are choosing to terminate the […]

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