ED MORRISSEY
The story turned out happier for the Chapmans — but only after her doctor convinced her to stop the abortion: Stanford University has three cases of mistaken abortions prompted by faulty results on this test. One of those actually was told that a follow-up test showed that the baby had no such defect, but was convinced that the first test was so accurate it couldn’t possibly have been wrong. But how exactly did doctors and patients get convinced so thoroughly that the tests are reliable? NECIR says it’s the sales pitch, because the FDA doesn’t actually vet the claims:
The screens are not subject to approval by the Food and Drug Administration. Because of a regulatory loophole, the companies operate free of agency oversight and the kind of independent analysis that would validate their accuracy claims. Doctors often get that information from salespeople, according todoctors themselves.
The errors go in the other direction, too. NECIR found women who had been assured that their babies were healthy when in fact they did have the genetic conditions for birth defects.
The blood tests have been designed to augment and perhaps eventually replace amniocentesis, which provides a highly accurate diagnosis but can create miscarriages on rare occasions. They screen for higher risk, and those testing positive are supposed to then have the amniocentesis to confirm. That would eliminate a significant number of unnecessary amnio tests and reduce the number of miscarriages as a result. Too many doctors and patients have treated the second test as optional, though, choosing instead to rely on a result that may not be accurate, from a test whose claimed accuracy may not withstand rigorous examination.
That is a tragedy for all involved, and one that should give all pause to consider what the sales pitch actually is for pre-natal testing such as this.