Duke study sheds light on smoking ban's effect on pregnant women

Duke University researchers have studied whether that ban has been beneficial for expecting mothers and their unborn child. Dr. Julia Schechter, a child and family clinical psychologist at Duke who led a study, confirmed that second-hand smoke was harmful to pregnant women.

"Women who are exposed to smoke during pregnancy are at higher risk for preterm birth, having a low-birth-weight baby and stillborn birth," she said, adding that the study also revealed negative long-term outcomes in children, many of whom were born with higher rates of ADHD and had learning difficulties later in life.

For the study, researchers worked through pregnancy clinics in North Carolina and other southeastern U.S. states and included 668 women in the research.

Scientists compared blood sample results of participants taken before and after the smoking ban was imposed.

"What we found was that rates of second-hand smoke exposure was lower -- significantly lower -- following the ban as compared to before the ban," Schechter said.

Researchers also identified clear racial and socioeconomic disparities.

Overall, she said the smoking ban had a positive impact on limiting exposure to pregnant woman. Researchers said they hope policy makers will consider expanding the ban to additional public places and even some non-public areas.