Breaking News: ACOG Issues New Guidelines on NIPT

Since the 1990’s, when fragments of cell free fetal DNA (cffDNA) were found in the mother’s blood stream, researchers have been on a quest for what is regularly termed “The Holy Grail” of prenatal testing: a diagnostic test from just a mother’s blood sample. If the fetal DNA could be identified and tested, then the fetus’ genetic code could be diagnosed. Mothers (and practitioners) would be able to receive a diagnosis without risking miscarriage, as must be done with current diagnostic tests, like amniocentesis (amnio) and chorionic villus sampling (CVS).

Current testing, however, can only provide a highly accurate recalculation of the probability that the fetus has Down syndrome. As a result, what had been hoped to be Noninvasive Prenatal Diagnosis (NIPD) can only be called Noninvasive Prenatal Testing (NIPT). On October 17, 2011, Sequenom, a publicly-traded testing laboratory, launched its MaterniT21 test in select markets. Soon thereafter followed private companies Ariosa and Verinata. With this new NIPT testing being available on the market, ACOG has issued a new committee opinion that will set the standard of care for the administration of NIPT.

ACOG Committee Opinion Number 545 is a brief statement on “Noninvasive Prenatal Testing for Fetal Aneuploidy.” In at least one other forthcoming post, I will detail my criticism of the new guidelines. But, let’s start with the positive. Here are the positives about the new guidelines:

1. Most importantly, the committee opinion emphasizes that NIPT “should not be a part of routine prenatal laboratory assessment but should be an informed patient choice after pretest counseling.” In a previous post, I addressed the concerns of routinization of prenatal testing. It is good that ACOG has made plain that even though NIPT poses hardly any immediate health risk to the mother, mothers should still be counseled about NIPT and make an affirmative, informed decision on whether to accept it.
2. ACOG also requires that practitioners inform the patients of the risk of false positives and false negatives. This, too, is a significant statement, because the testing laboratories marketing materials highlight how accurate their tests are. Simply reading a pamphlet, and not knowing more about the testing, a mother might reasonably believe a test result of Down syndrome was a diagnosis. Even more significant, however, is the requirement to inform patients of the risk of false negatives. In studies on NIPT, there were no false negatives, causing some to believe that NIPT could at least be relied on for diagnosing that the fetus does not have Down syndrome. The ACOG statement now requires that because a risk remains, patients should be informed that there is still a risk that a negative test is, in fact, false.
3. ACOG states that after a positive NIPT test, patients “should be referred for genetic counseling and offered invasive prenatal diagnosis for confirmation of test results.” This requirement reinforces the point that patients should not make decisions on whether to continue or terminate a pregnancy based solely on an NIPT test result. Instead, those results need to be confirmed through an amnio or CVS. Moreover, the decision to have prenatal diagnostic testing should come after receiving genetic counseling and again, a CVS or amnio is to only be offered, meaning the mother should again exercise affirmative informed choice about whether to undergo such testing.
4. Lastly, the ACOG committee opinion is significant for limiting the offering of NIPT to only “high-risk” women, and explicitly stating that NIPT “should not be offered to low-risk women or women with multiple gestations because it has not been sufficiently evaluated in these groups.” Since Sequenom introduced its test to the market, there were anecdotal reports of practitioners routinely offering NIPT to all of their patients, regardless of their probability of having a child with Down syndrome. The population of expectant mothers who are high risk are only those who meet one of these criteria (listed in the ACOG statement): 35 years old or older; having a fetal ultrasound indicating increased probability; having another prenatal test result indicating higher probability; having had a prior pregnancy with a child with DS; or, the parent has balanced translocation. Until this statement is changed, then, insurance or governmental medical plans should not provide coverage for NIPT unless the expectant mother is in the much smaller population of those considered “high-risk.”

Like I said, I’ll have a follow up post in the coming days detailing the criticisms of this statement, but these are the positives. For this post’s question I invite you to share your thoughts–positive, negative, or ambiguous–about the new statement. These comments will help inform the future post’s criticism of the statement.