Yale scientists have devised a test for fetal anemia that eliminates the risks of invasive procedures such as amniocentesis or cordocentesis. The test uses Doppler ultrasound to measure fetal blood velocity in the cerebral circulation. Anemic fetuses have a higher blood flow velocity in arteries and veins. “Invasive procedures place the fetus in unnecessary danger,” said Giancarlo Mari, M.D., associate professor of obstetrics and gynecology and lead author of the study. “In more than 70 percent of cases, the fetuses tested were either non-anemic or mildly anemic, and an invasive procedure could have been either avoided or delayed.” The study was published in the Jan. 6 issue of The New England Journal of Medicine.