Racial differences in fetal growth.

• Position: NIH

Current standards for ultrasound evaluation of fetal growth may lead to misclassification of up to 15% of fetuses of minority mothers as being too small, according to a study by researchers at the National Institutes of Health, Bethesda, Md., and other institutions. Fetal growth restriction is a medical term used to describe fetuses that do not keep up with growth milestones appropriate to their stage of development. Growth restriction is a sign of an underlying health problem, often resulting from the fetus not receiving enough nutrients or oxygen in the uterus.

According to the latest study, however, many fetuses of minority mothers may be developing normally but, because of hereditary and environmental factors, they are smaller than their white counterparts. The findings could mean that many otherwise healthy pregnant women are subjected to unncessary tests and procedures.

"Doctors like to be proactive--if they suspect there's a problem with a fetus' growth, they're likely going to order tests and investigate," explains first author Germaine Louis, director of the Division of Intramural Population Health Research at the National Institute of Child Health and Human Development. "However, inaccurate standards may be leading women to receive unnecessary tests --and...