A University of Queensland-led study has failed to find any strong links between drinking coffee during pregnancy and neurodevelopmental difficulties in children, but researchers are advising expectant mothers to continue following medical guidelines on caffeine consumption.

Dr. Gunn-Helen Moen and Ph.D. student Shannon D’Urso from UQ’s Institute for Molecular Bioscience (IMB) led an in-depth genetic analysis of data from tens of thousands of families in Norway.

The research was published in Psychological Medicine,

“Scandinavians are some of the biggest coffee consumers in the world, drinking at least 4 cups a day, with little stigma about drinking coffee during pregnancy,” Dr. Moen said. “Our study used genetic data from mothers, fathers and babies as well as questionnaires about the parents’ coffee consumption before and during pregnancy.

“The participants also answered questions about their child’s development until the age of 8, including their social skills, motor skills, language and indicators of ADHD and autism. Our analysis found no link between coffee consumption during pregnancy and children’s neurodevelopmental difficulties.”

The researchers said physiological changes during pregnancy prevent caffeine breaking down easily and it can cross the placenta and reach the fetus, where there are no enzymes to metabolize it.

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

“We used a method called Mendelian randomization, which uses genetic variants that predict coffee drinking behavior and can separate out the effect of different factors during pregnancy,” she said. “It mimics a randomized 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 pregnancy.”

The researchers used genetic analysis to understand complex traits and diseases especially in early life, with a previous study by Dr. Moen showing that drinking coffee in pregnancy did not affect birth weight, risk of miscarriage or stillbirth.

The researchers emphasize the importance of following advice from health care providers to limit caffeine consumption during pregnancy, as caffeine may influence other pregnancy outcomes.

They are now looking to apply similar analyzes to understand more about genetic and environmental causes of neurodiversity, and the effect on it from other factors on brain development during pregnancy.

The research team included international collaborators in Norway and England as well as IMB’s Caroline Brito Nunes, Dr. Daniel Hwang and Professor David Evans.