Does drinking coffee during pregnancy really affect a child’s neurodevelopment? New study says likely not

By Dr. Chinta SidharthanReviewed by Lily Ramsey, LLMOct 14 2024

Despite previous concerns, new research finds little evidence of a direct causal link between maternal coffee consumption and childhood developmental challenges.

Study: Mendelian Randomization Analysis of Maternal Coffee Consumption During Pregnancy on Offspring Neurodevelopmental Difficulties in the Norwegian Mother, Father and Child Cohort Study (MoBa). Image Credit: MVelishchuk/Shutterstock.com

A recent study published in Psychological Medicine examined a Norwegian parent-child cohort to determine whether coffee consumption by the mother during pregnancy impacts the neurodevelopment of the fetus and could be linked to neurodevelopmental difficulties in the offspring.

Background

Coffee is a beverage widely consumed worldwide, even during pregnancy. Studies show that daily coffee consumption in Scandinavian countries often exceeds an average of 400 mg of caffeine, which is equal to four cups a day.

Although pregnant women are not restricted from consuming coffee, the metabolism of caffeine is known to slow down significantly due to the physiological changes that occur during pregnancy.

Furthermore, caffeine metabolites such as theophylline and paraxanthine can easily cross the placenta into the fetus, and because the caffeine metabolizing enzymes are underdeveloped in the fetus, the accumulation of caffeine and its metabolites can impact brain development in the fetus.

The findings on the impact of caffeine consumption during pregnancy on fetal brain development have also been mixed, with some studies showing no correlation. In contrast, others indicate a strong relationship between caffeine and neurodevelopmental difficulties in the fetus.

One of the major factors for this lack of clarity in the findings is the confounding effects of factors such as smoking and alcohol consumption, which are often not reported by participants because of the stigma associated with these lifestyle factors during pregnancy.

About the study

In the present study, the researchers applied a Mendelian randomization approach, which used genetic variants associated with caffeine metabolism to examine the potential causal relationship between caffeine consumption by the mother during pregnancy and neurodevelopmental difficulties in the fetus.

The Mendelian randomization approach also allows effective control of confounding variables. The study used the Norwegian Mother, Father, and Child Cohort, which provided data for over one million children and more than 95,000 and 75,000 mothers and fathers, respectively.

The data comprised blood samples collected from both parents during pregnancy and mother and child at birth, as well as cleaned and processed genetic data.

The neurodevelopment of the child was rated and reported by the mothers at various points during the child’s development up to the age of eight years. Various scales involving measurements of motor skills, language, social communication, and behavior were used to assess the child’s neurodevelopment.

Self-reported measures of coffee intake by the mothers and fathers were obtained, and the average caffeine consumption from coffee, tea, and energy drinks was calculated.

Furthermore, various questionnaires were also administered to obtain information on alcohol consumption, smoking, and socioeconomic variables such as income and education levels.

The researchers conducted a principal component analysis to reduce the number of variables involved in the analysis and to manage the large number of correlated neurodevelopmental traits.

They then used a linear regression model to analyze the relationship between coffee consumption by the parents and neurodevelopmental traits in the offspring.

The analyses were adjusted for potential confounders such as the age of the parents, smoking, alcohol intake, and education levels.

The Mendelian randomization analysis incorporated genetic data to assess the causal relationship between maternal coffee consumption and neurodevelopmental outcomes in the child.

Study findings

The researchers found that increased intake of coffee by the mother during pregnancy was associated with several neurodevelopmental difficulties in the offspring. Still, many of these associations disappeared when the analyses were adjusted for potential confounders such as alcohol intake, smoking, income, and education levels.

However, after the analyses were adjusted for confounding variables, significant associations were noted between maternal coffee intake and social communication and motor difficulties at age three and hyperactivity when the child was five years old.

The Mendelian randomization analysis did not provide any evidence for a causal relationship between increased coffee consumption by the mother and neurodevelopmental delays or difficulties in the child.

Furthermore, the results also suggested the possibility of pleiotropy, indicating that other genetic factors could be influencing any observed patterns.

The genetic analysis also showed that the genetic variants related to coffee consumption were associated with alcohol intake and smoking behavior in mothers, further complicating the interpretation of the findings.

These observations emphasized the role of confounding factors in this association. They highlighted the need for further investigation into various other factors, including coffee components other than caffeine and coffee metabolism pathways.

Conclusions

To summarize, although an initial association was observed between maternal coffee intake and neurodevelopmental difficulties in children, the Mendelian randomization analysis suggested that various other confounding variables, including smoking and alcohol intake, were influencing the relationship.

The researchers concluded that there was limited evidence for a causal relationship between coffee intake in parents and neurodevelopmental delays in their offspring.