By Dr. Brian McDonough

PHILADELPHIA (CBS) - New research finds women who live in areas with poor air quality could be at higher risk of having a baby with health problems.

Researchers at the journal Environmental Health Perspectives looked three billion births across nine countries and what they found is that women exposed to high levels of air pollution are at greater risk of having unhealthy babies or at least babies with low birth weight.

Low birth weight is associated with increased infant mortality and other health risks.