1. Almost one in five mothers in Ireland smoke during pregnancy

Comparisons of prenatal smoking between the Child and Infant Cohorts suggest that the proportion of mothers smoking during pregnancy has decreased by over 37 per cent since the late 1990s, yet almost 18 per cent of mothers of the Infant Cohort reported smoking at some stage during their pregnancy, and 13 per cent all the way through. Women from lower income and social-class households and those with lower levels of education were significantly more likely to smoke during pregnancy. Smoking was also strongly related to the woman’s experience of psychological stress, anxiety and depression, higher numbers of previous children, having a partner who smokes and having weaker pregnancy intentions; i.e. the pregnancy was unintended or not intended at the time. Women experiencing a great deal of stress during pregnancy were almost 40 per cent more likely to smoke during pregnancy. Women who had previously had children were less likely to quit during pregnancy, as were those with lower levels of education and women who lived with a partner who smoked.

2. A complex pattern of alcohol consumption during pregnancy

Abstinence from drinking alcohol during pregnancy was less likely among older women and those with higher levels of education, higher social class and income. Women aged 35 to 39 were 33 per cent more likely to drink during pregnancy than women aged under 25. Women having their second or third child were over 25 per cent more likely. However, older age, higher income, class and education also tended to be associated with more moderate drinking compared to younger women and those with lower levels of income and education. Compared to UK studies, women were significantly less likely to report drinking during pregnancy, but if they did consume, they were more likely to drink more heavily than their UK counterparts. The average number of units of alcohol consumed during pregnancy was highest in the first trimester but consumption fell after confirmation of the pregnancy. Younger and less educated women tended to drink more in early pregnancy but their consumption fell quickly in the second or third trimesters, whereas consumption among more advantaged women often increased over the pregnancy. Having had children previously was also associated with a higher prevalence of drinking, suggesting that the perception of risk falls with experience.