New research has failed to find strong links between drinking coffee during pregnancy and neurodevelopmental difficulties in children. However, researchers are advising expectant mothers to follow current medical guidelines on caffeine consumption.  

 
University of Queensland researchers conducted an in-depth genetic analysis of data from tens of thousands of families in Norway.  

“Scandinavians are some of the biggest coffee consumers in the world, drinking at least four cups a day, with little stigma about drinking coffee during pregnancy,” said UQ lead researcher Dr Gunn-Helen Moen. 
 
The UQ research team used genetic data from mothers, fathers and babies as well as questionnaires about the parents’ coffee consumption before and during pregnancy. Study participants answered questions about their child’s development until the age of eight, including their social, motor and language skills. 

 “Our analysis found no link between coffee consumption during pregnancy and children’s neurodevelopmental difficulties,” said Dr Moen.

 Physiological changes during pregnancy prevent caffeine breaking down easily and it can cross the placenta and reach the foetus, where there are no enzymes to metabolise it. 

Current Australian guidelines experts recommend having no more than 200 milligrams (mg) of caffeine a day during pregnancy to reduce the risk of miscarriage, low birth weight neonates and pregnancy complications. This equates to roughly two cups of moderate-strength coffee or one cup of strong espresso style coffee. 

Caffeine accumulation has been thought to impact the developing foetal brain, however previous observational studies couldn’t account for other environmental factors such as alcohol, cigarette smoke or poor diet, said Dr Moen. 

UQ researchers used a method called Mendelian randomisation, which uses genetic variants that predict coffee drinking behaviour and can separate out the effect of different factors during pregnancy. The method mimics a randomised controlled trial without subjecting pregnant mothers and their babies to any ill effects. 
 
“The benefit of this method is the effects of caffeine, alcohol, cigarettes and diet can be separated in the data, so we can look solely at the impact of caffeine on the pregnancy,” said Dr Moen. 
 
The genetic analysis to understand complex traits and diseases especially in early life builds on a previous study conducted by Dr Moen showing that drinking coffee in pregnancy did not affect birth weight, risk of miscarriage or stillbirth. 

However, the researchers emphasise the importance of following advice from healthcare providers to limit caffeine consumption during pregnancy, as caffeine may influence other pregnancy outcomes. 
 
The research paper was published in journal Psychological Medicine.