Can polluted air cause birth defects?

Scientists have found new evidence that prenatal exposure to air pollution may cause congenital heart defects. However, inconsistencies with past results make the finding less than definitive, the researchers say.

Epidemiologist Pauline Mendola of the Environmental Protection Agency in Research Triangle Park, N.C., and her collaborators compared pollution statistics and records of births between 1997 and 2000 in seven Texas counties.