When Ramona Burton became pregnant with her second child this year, the 37-year-old knew that her age put her baby at an elevated risk for
Burton and her husband didn't want to risk
Three versions of this test, which can be performed as early as 10 weeks into a pregnancy, have come onto the market since December 2011.
Tens of thousands of women have used them, according to the companies that sell the tests. But they are not subject to regulation by the
New medical technologies often challenge a health-care industry grappling with pressures to control costs. It's not yet clear whether the new tests will cut costs and miscarriages by reducing invasive prenatal diagnostic procedures such as amniocentesis or inflate costs because they're used by women who probably would never have opted for amnio because of miscarriage fears.
Behind the test
With the new tests, fragments of fetal DNA extracted from the mother's blood sample are checked for increased amounts of material from chromosomes 21, 18 and 13, a sign that the fetus carries three instead of the normal two copies of those chromosomes.
In this case, more is not better. Having an extra copy of 21, a condition called trisomy 21, is the main cause of Down syndrome, while having a third copy of 18, a condition called trisomy 18, causes a less common disorder named
Standard first-trimester screening for these
The new blood tests that assess fetal DNA rather than maternal blood perform better than standard screening, says Tufts scientist Diana Bianchi, whose research helped lay the groundwork for them. Bianchi sits on the scientific advisory board of Verinata Health, which launched its test, called Verifi, in March. "The problem is they're more expensive, so they can't be a primary screen," she says.
The tests generally are offered only to women whose age, family history or standard screening puts their fetus at a higher risk of having a chromosome abnormality — not to all women, as the standard screening tests are.
So far, major insurance companies, citing limited studies about the tests' accuracy and impact on patient care, consider them to be experimental and do not cover them.
The American College of Obstetricians and Gynecologists published its first opinion on the tests Nov. 20 and concluded they "should not be part of routine prenatal laboratory assessment." However, ACOG said, the tests can be offered to patients at increased risk of having a baby with a trisomy, as long as they are counseled beforehand about the tests' limitations. Previously, the National Society of Genetic Counselors and the International Society for Prenatal Diagnosis reached similar conclusions.
Because research has not yet proved that the new tests are as accurate as the standard invasive tests, all three organizations recommend that women with a positive result undergo amniocentesis or chorionic villus sampling to be sure.
For now at least, the companies that market the new tests appear to be eating much of the cost. For example, the most that women with insurance have to pay out of pocket is $235 for the MaterniT21 Plus test (list price $1,900) and $200 for Verifi (list price $1,200), even if their plan declines to cover the test. Both companies offer self-pay options for women without insurance: The price is $450 to $500 for MaterniT21 Plus and an "introductory price" of $495 for Verifi.