New test for Down syndrome
A new, noninvasive screening test for Down syndrome would allow some women with high-risk pregnancies to avoid amniocentesis and in the future may provide detection early enough for treatment to improve some babies’ cognitive function, a Tufts University neonatal genetics expert told a symposium at Harvard Medical School on Tuesday. Physicians recommend that all pregnant women undergo initial screening for Down syndrome, and it is recommended that those with positive results undergo amniocentesis, in which a long needle is inserted into the mother’s uterus to extract cells in the fluid around the fetus. Those alternate screening tests miss 8 percent of Down syndrome cases, however, and also give false positive results about 5 percent of the time. That means that some women may undergo further amniocentesis, which, in addition to being invasive, bears a slight risk of causing miscarriage. The new test, according to Diana Bianchi, executive director of Tufts Medical Center’s Mother...