Health
Study Links Maternal Anaemia to Reduced Brain Size in Infants
By Kat Lay
New research indicates that babies born to mothers with anaemia during pregnancy tend to have smaller brains, particularly in regions associated with movement, learning and emotional regulation. Scientists say these differences, observable from as early as one year of age, may contribute to cognitive difficulties once children reach school age.
Anaemia, often caused by iron deficiency, affects more than a third of pregnant women globally, with the highest rates found in sub-Saharan Africa and South Asia. The condition, marked by lower-than-normal red blood cell counts, can cause fatigue, breathlessness and dizziness.
A team from King's College London and the University of Cape Town studied over 300 mothers and their infants in Cape Town, conducting multiple brain scans between three months and two years of age. They found that, on average, babies born to anaemic mothers had brain volumes 4% smaller than those born to mothers without the condition—even though all the anaemic mothers had only mild cases.
The study identified specific differences in three brain regions: the putamen, caudate nucleus and corpus callosum. According to Jessica Ringshaw, lead researcher at King's Institute of Psychiatry, Psychology & Neuroscience and the University of Cape Town, these areas are tied to important neuropsychological functions such as processing speed, emotional control and executive function.
The gap in brain development between the two groups grew over time. For example, the corpus callosum was about 4% smaller at 12 months in babies from anaemic pregnancies, but this difference increased to 6% by 24 months. Previous South African studies on older children found similar patterns, suggesting the effects persist rather than resolve with age. Ringshaw noted that these differences remain evident even when children begin school at age six, potentially contributing to cognitive challenges at that stage.
The findings may help explain earlier research showing that children born to anaemic mothers often perform worse on developmental assessments. Ringshaw said the mothers in both groups—anaemic and non-anaemic—had similar backgrounds in terms of income and food security, strengthening the case that anaemia itself was responsible for the brain differences observed.
She emphasized the need for better anaemia screening, especially during pregnancy, and recommended iron supplementation—oral or intravenous—where appropriate. Ringshaw noted that anaemia can stem from various causes, including infections, pointing out that the study found higher anaemia rates among women living with HIV. This, she said, highlights the importance of combining iron treatment with proper management of underlying infections.
Although the World Health Organization has identified anaemia reduction as a global health priority, progress has slowed over the past two decades. Ringshaw stressed that addressing anaemia should be a central focus of public health initiatives to support children's healthy development.
The study, published in the journal Brain Communications, also tested a new generation of portable, low-cost MRI scanners. Researchers compared results from these devices with those from traditional high-field MRI machines and found the portable scanners were equally capable of detecting brain differences linked to maternal anaemia.
Steve Williams, professor of neuroimaging at King's College London, said the study demonstrated that the new technology could effectively measure the effects of malnutrition on brain development, even in resource-limited settings, providing an efficient way to evaluate future health interventions.