The number of women who smoke during pregnancy has fallen in Ireland in recent years, however for those who continue the habit while pregnant, new research has shown potentially serious consequences for their children.
The research is based on data from Growing Up In Ireland, an ongoing study of almost 20,000 children and their families. It reveals that the number of mothers who smoke during pregnancy has fallen from 28% in the late 1990s to just over 17% now. At least one in four smokers quit during early pregnancy and women are more likely to quit if they have a higher household income and a higher education level.
However, those who continue to smoke throughout pregnancy are more likely to have children with behavioural problems. In fact, the children of smokers are 1.4 times more likely to be defined as having a behavioural problem by their teachers compared to the children of non-smokers.
Furthermore, the problem appeared to be directly linked to the amount the mother smoked during pregnancy. Overall, the children of women who smoked occassionally while pregnant were 32% more likely to show behavioural problems compared to the children of non-smokers. However, this figure rose to 78% for the children of heavy smokers.
Heavy smoking was defined as 11 or more cigarettes per day.
According to one of the research's authors, Dr Cathal McCrory of Trinity College Dublin, while it has long been known that smoking during pregnancy increases the risk of premature births and low birth weights, 'the results of this study show that the effects of smoking during pregnancy are long-lasting and can affect aspects of the child's emotional and behavioural development in later life'.
"These findings reinforce the need for programmes aimed at promoting successful cessation of smoking during what is a critical period for the developing infant," he said.
The Growing Up In Ireland study is being carried out by a number of researchers, led by Trinity College Dublin and the Economic and Social Research Institute (ESRI).