Washington, March 1 (IANS) Children born to pregnant women who have been smoking in the first three months of their pregnancy may suffer from heart defects, a study has found.

The study conducted by the US Center for Disease Control and Prevention (CDC), has found that women who smoke in the first trimester face a 20 to 70 percent greater likelihood that a baby would be born with congenital heart defects.

Congenital heart defects are the most common type of birth defects, contributing to approximately 30 percent of infant deaths from birth defects annually, Xinhua reported.

The study has found a link between tobacco exposure and certain types of defects such as those that obstruct the flow of blood from the right side of the heart into the lungs and openings between the upper chambers of the heart.

‘Women who smoke and are thinking about becoming pregnant need to quit smoking, and if they’re already pregnant, they need to stop,’ says CDC Director Thomas R. Frieden.

‘Quitting is the single most important thing a woman can do to improve her health as well as the health of her baby.’

‘Successfully stopping smoking during pregnancy also lowers the chances of pregnancy complications such as preterm delivery and that an infant will have other complications such as low birth weight,’ says Adolfo Correa, medical officer in CDC’s National Centre on Birth Defects and Developmental Disabilities.

The findings of the study, Maternal Smoking and Congenital Heart Defects in the Baltimore-Washington Infant, are based on the cases of congenital heart defects in the US.

Infants born from 1981-1989 were included in the analysis.

Congenital heart defects are conditions present at birth that decrease the ability of the heart to work well, which can result in an increased likelihood of death or long-term disabilities. They affect nearly 40,000 infants in the US annually.

The study was published Monday in the journal Pediatrics, the official journal of the American Academy of Paediatrics.