A research has found that children with heart defects were more likely to have been born to mothers who smoked, and the risk was highest in the heaviest smokers.

 

 Patrick M. Sullivan, clinical fellow in paediatric cardiology at Seattle Children's Hospital, said: "Our research provides strong support for the hypothesis that smoking during pregnancy increases the risk of specific heart defects".

 

 Older women had a higher risk of having a child with a heart defect if they smoked. Cigarette smoking during pregnancy has been linked to many birth defects, such as cleft lips, cleft palates, and missing or deformed limbs.

 

 For the study, researchers used birth certificate data and hospital discharge records from Washington in the US. The researchers identified 14,128 children born with a variety of heart defects between 1989-2011.

 

 Newborns whose mothers smoked were at about a 50 to 70 percent greater risk for anomalies of the valve and vessels that carry blood to the lungs (pulmonary valve and pulmonary arteries). They were at about 20 percent greater risk for holes in the wall separating the two collecting chambers of the heart (atrial septal defect).

 

 All of these defects often require invasive procedures for correction.