Maternal Caffeine Intake and Fetal Developmental Outcomes

Maternal caffeine consumption is ubiquitous worldwide and has been scrutinised for its potential impact on fetal growth, gestational duration and neurodevelopment. Caffeine readily crosses the placenta and reaches fetal circulation, where immature enzymatic systems prolong its half-life. Proposed mechanisms include adenosine receptor antagonism, altered placental blood flow and modulation of maternal and fetal glucocorticoid metabolism. Epidemiological studies report associations between higher maternal intake—often defined as exceeding 200 mg per day—and reduced birth weight, increased risk of small for gestational age (SGA) and fetal growth restriction (FGR). However, these findings have been inconsistently replicated and often confounded by smoking, diet or socio-economic factors. Animal models suggest that in utero exposure can programme the hypothalamic-pituitary-adrenal axis and cardiovascular function in offspring, implying long-term health implications. Current guidelines generally advise limiting caffeine to low or moderate levels before and throughout pregnancy. Ongoing research aims to disentangle causal effects from correlated lifestyle exposures and to identify sensitive windows during which caffeine exerts the greatest influence on developmental trajectories.

Research from Nature Portfolio

A cross-sectional survey of pregnant women in Ibadan, Nigeria, examined kolanut use—a culturally important caffeine source—and found that one in three women consumed kolanut during pregnancy, often in high quantities to relieve nausea and vomiting. Usage varied by ethnicity and education, underscoring the role of cultural practices in caffeine exposure. In a rat model of prenatal caffeine exposure (120 mg/kg daily), offspring exposed in utero exhibited altered adrenal steroidogenesis under high-fat diet and chronic stress. Under normal diet, corticosterone levels were suppressed, whereas stress elicited exaggerated glucocorticoid responses. These findings implicate programming of the glucocorticoid–insulin-like growth factor 1 axis in mediating long-term endocrine and metabolic adaptations following maternal caffeine intake.

Maternal Caffeine Intake and Fetal Developmental Outcomes publication trend

The graph below shows the total number of articles in maternal caffeine intake and fetal developmental outcomes across all publications each year (not limited to Nature Index journals).

Technical terms

Caffeine clearance: The efficiency of metabolic pathways, notably cytochrome P450 enzymes, by which caffeine is eliminated; clearance rates slow in pregnancy.

Paraxanthine: The principal metabolite of caffeine, measured to quantify objective exposure through maternal serum.

Fetal growth restriction (FGR): A pathological condition in which a fetus fails to achieve its genetically dictated growth potential, often diagnosed by customised birth weight centiles.

Mendelian randomisation: A genetic epidemiology method using inherited variants as proxies for exposures to infer causality while reducing confounding.

Glucocorticoid–IGF1 axis: The regulatory network between stress hormones and insulin-like growth factor 1 that influences fetal organ development and postnatal metabolic homeostasis.

References

1. Prevalence and consumption pattern of kolanut among pregnant women in Ibadan metropolis. Scientific Reports (2023).
2. High-fat diet and chronic stress aggravate adrenal function abnormality induced by prenatal caffeine exposure in male offspring rats. Scientific Reports (2017).
3. Objective measures of smoking and caffeine intake and the risk of adverse pregnancy outcomes. International Journal of Epidemiology (2023).
4. Mendelian randomization analysis of maternal coffee consumption during pregnancy on offspring neurodevelopmental difficulties in the Norwegian Mother, Father and Child Cohort Study (MoBa). Psychological Medicine (2024).
5. Maternal caffeine intake during pregnancy and risk of fetal growth restriction: a large prospective observational study. The BMJ (2008).
6. Caffeine-Induced Activated Glucocorticoid Metabolism in the Hippocampus Causes Hypothalamic-Pituitary-Adrenal Axis Inhibition in Fetal Rats. PLOS ONE (2012).
7. Embryonic Caffeine Exposure Acts via A1 Adenosine Receptors to Alter Adult Cardiac Function and DNA Methylation in Mice. PLOS ONE (2014).