Drinking coffee during pregnancy may not be as risky as once thought, according to a recent study that found no strong link between caffeine consumption and neurodevelopmental problems in children.

Despite these reassuring findings, the researchers still recommend that pregnant people stick to medical advice on caffeine limits.

The observational study, published Oct. 9 in Psychological Medicine, suggested that drinking a moderate amount of coffee during pregnancy is unlikely to have a significant effect on a child’s brain development.

“Our analysis found no link between coffee consumption during pregnancy and children’s neurodevelopmental difficulties,” said co-author Gunn-Helen Moen, from the University of Queensland’s Institute for Molecular Bioscience.

“Overall, our study supports current clinical guidelines that state low to moderate consumption of coffee during pregnancy is safe for the mother and developing baby,” Moen said in an accompanying commentary article on Oct. 14.

These findings echo the advice from the Public Health Agency of Canada (PHAC), which states drinking caffeine while pregnant is safe in small amounts.

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The current PHAC guidelines recommend keeping caffeine intake below 300 milligrams a day, which amounts to around two cups of coffee. This includes coffee, tea (including black, oolong, white and green tea), caffeinated soft drinks (cola beverages) and energy drinks, chocolate and herbs such as guarana and yerba mate.

HealthLinkBC also states that small amounts of caffeine are safe for the fetus. It’s recommended to keep caffeine intake below 300 mg per day, as higher levels of caffeine may be associated with an increased risk of miscarriage, it stated.

“There are no studies to show that it has a detrimental effect on the fetus. And I generally say one to one to two cups per day is fine,” explained Dr. Lynn Murphy-Kaulbeck, a maternal-fetal medicine specialist and president of the Society of Obstetricians and Gynecologists of Canada (SOGC).

She noted that some studies suggest high caffeine intake very early in pregnancy — equivalent to six, seven, or eight cups a day — may be a risk factor for miscarriage. But that is in high amounts.

Prior studies have suggested increased coffee consumption during pregnancy is associated with the child having neurodevelopmental difficulties, such as attention-deficit hyperactivity disorder (ADHD).

This is because caffeine and its main byproducts (paraxanthine, theophylline and theobromine) can easily pass through the placenta to the fetus. And because the fetus does not yet have fully developed enzymes to break down caffeine, the concern has long been that it could potentially accumulate in the system and negatively affect the developing fetal brain.

Coffee and caffeine consumption are often linked with other factors like age, smoking and alcohol use, which may not have been accurately considered in previous studies about fetal development risks.

Because of this researchers then aimed to find out whether coffee was the actual cause of these risks or if other factors were involved.

To do this, the study looked at tens of thousands of families registered in the Norwegian Mother, Father and Child Cohort Study. All pregnant women in Norway between 1999 and 2008 were invited to participate and 58,694 women took part with their child.

“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,” Moen said in a media release.  “Our study used genetic data from mothers, fathers and babies as well as questionnaires about the parents’ coffee consumption before and during pregnancy.

Parents were asked about their coffee consumption before and during pregnancy, as well as their child’s neurodevelopmental traits from six months to eight years of age. The participants also provided genetic samples, which enabled researchers to control for genetic variants shared between mothers and children, allowing for a clearer analysis of the effects of coffee drinking, the study stated.

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Without adjusting for potential confounding factors such as maternal smoking, alcohol consumption, and parental education and income, the researchers found a link between higher maternal coffee consumption and various neurodevelopmental difficulties in offspring.

However, after accounting for potential confounding factors, the previously significant effects of maternal coffee consumption on neurodevelopmental problems in offspring diminished to nearly zero.

“Our MR analyses found little evidence for a causal effect between maternal coffee consumption and most offspring neurodevelopmental difficulties,” the study concluded.

The researchers concluded there were limitations to the study, as it was only able to rule out strong effects on neurodevelopmental difficulties, and it is possible small effects may exist. Coffee consumption during pregnancy could impact others and children in other ways.

The study also emphasized the need for additional research on this topic to gain a better understanding of how maternal coffee consumption impacts child development. However, in the meantime, the researchers said that low to moderate consumption of coffee during pregnancy is safe for the mother and developing baby.

“I think women need to hear that’s OK to drink a coffee while pregnant,” Murphy-Kaulbeck said. “They don’t need to worry; in fact, they should enjoy it.”