Mothers: Too Much Prenatal Testing Info is “Toxic”

Bioethics   |   Rebecca Taylor   |   Sep 25, 2012   |   3:06PM   |   Washington, DC

“TMI! Mom. TMI!” I hear that phrase a lot with a couple of teenagers in my house. TMI, of course, is short for “too much information.”

A new study is showing that there is such a thing as TMI in prenatal genetic testing. Now I am a proponent of prenatal genetic testing when it is appropriate for the health and well-being of the child. I think it is a powerful tool that proves beyond a shadow of a doubt that a distinct human life is growing inside the womb. Just because abortion-on-demand (the real killer of the unborn) is the law of the land does not mean prenatal testing is inherently evil.

But there is such a thing as too much information, especially if that information has no clinical value. There is a lot about genetics that remains a mystery. Just because a genetic anomaly is found does not mean doctors know what that anomaly means if anything.

A new type of genetic testing called micro-array testing looks at a person’s entire genome (all of their DNA) looking for abnormalities. It is a powerful tool for doctors who have a child with unexplained developmental delay or other undiagnosed problems.

But for an unborn child, a micro-array analysis may reveal genetic abnormalities that have no clinical significance, meaning that scientists do not know if these genetic anomalies will cause problem or what those problems might be. Not all genetic mutations cause disease.

And telling mom about her child’s results that have uncertain clinical significance just makes her stressed out and anxious. Researchers at Perelman School of Medicine at the University of Pennsylvania asked mothers who got ambiguous results through micro-array how they felt about them. The moms called the results “toxic knowledge.” From News-Medical:

We often hear that “knowledge is power.” But, that isn’t always the case, especially when the knowledge pertains to the health of an unborn child, with murky implications, at best. A new study, led by researchers from the Perelman School of Medicine at the University of Pennsylvania, begins to document this exception to the general rule.

Barbara Bernhardt, MS, CGC, a genetic counselor at the Hospital of the University of Pennsylvania, and colleagues contacted a small group of women who are participating in a larger Columbia University study investigating the use of a genetic test called a DNA microarray to identify the possibility of prenatal chromosomal abnormalities. Bernhardt is also co-director of the Penn Center for the Integration of Genetic Healthcare Technologies.

The study’s goal: To document a woman’s experience upon learning that her child’s genetic material contained chromosomal abnormalities. The women’s responses to this type of news were mostly negative, ranging from saying they “needed support” after getting the results to describing the results as “toxic knowledge,” that they wish they hadn’t received….



Women had difficulty making sense of the test results, as copy-number variants are often of either uncertain clinical significance, or produce a wide array of possible developmental outcomes. As a result, the women’s time-critical and emotionally charged decisions about whether to terminate a pregnancy, for instance, were complicated….

The women noted that in many cases the array results constituted “toxic knowledge” that they, in retrospect, wish they hadn’t learned, because it negatively impacted their pregnancy, birth, and postnatal experiences. As Bernhardt describes it, “They watch their babies like hawks, – always waiting for the other shoe to drop.”

So while micro-array analysis is appropriate for a child that is clearly demonstrating signs of a problem, it is not appropriate for the unborn that maybe perfectly healthy despite test results that show possible genetic anomalies. And stressing out mom while she is pregnant is never a good idea.

In other words, TMI doctor. TMI.