An Australian Rotary Health and NHMRC funded study published recently has reported that there was no harmful effect of low-level alcohol use by mothers during pregnancy on infants’ cognitive ability at 12-months of age.
The research was conducted at the University of New South Wales’ National Drug and Alcohol Research Centre and the National Drug Research Institute, Curtin University. The study followed a cohort of over 1600 pregnant women and their partners from pregnancy, interviewed them about alcohol use, and conducted infant development assessments with infants at 12-months of age.
2013 Ian Scott PhD Scholarship recipient Clare McCormack, who conducted her PhD research on the project, found more than 65% of women and 84% of partners drank alcohol during pregnancy, but most women significantly reduced or stopped drinking after the first 6 weeks.
“Results also showed that there was no harmful effect of low-level alcohol exposure – less than 7 standard drinks per week, and not more than 2 standard drinks per occasion – on infant cognitive ability at 12-months of age,” Clare said.
Interestingly, women who drank alcohol tended to have higher household incomes, were more highly educated, were more likely to be of English-speaking backgrounds, and to have had unplanned pregnancies, than those who did not drink.
“These factors are important to consider, because children whose mothers drank alcohol during pregnancy are more likely to be raised in relatively advantaged households. However, even when taking these factors into account, no harmful effects of alcohol exposure were seen.”
These findings add to current knowledge that there is little evidence for harm associated with low-level alcohol exposure, while highlighting the challenges of studying these effects in humans. Because it is impossible to conduct experiments, the “true” effect of drinking during pregnancy is difficult to determine.
The authors caution however that the NHMRC guidelines recommend not drinking at all during pregnancy.
“The best course of action is not to drink during pregnancy,” Clare said.
“However, the study gives us useful information about the complex interactions between alcohol, early childhood development and other social and economic factors.
“It also provides some reassurance for women who may have been drinking before they were aware of their pregnancy or who may have very occasionally consumed alcohol.”
Australian Rotary Health has continued funding the longitudinal study in 2018 after awarding a Mental Health Grant to Dr Delyse Hutchinson, Project Co-ordinator of the Triple B Pregnancy Cohort Study and Senior Research Fellow at the Centre for Social and Early Emotional Development, Deakin University.