A new study has found that babies born to mothers with anaemia have brain volumes roughly 4% smaller than those of other infants, with differences concentrated in regions linked to movement, learning, and emotional regulation. Researchers from King's College London and the University of Cape Town followed more than 300 mother-infant pairs in South Africa, scanning infant brains multiple times between three months and two years of age, and found the gap widened over time rather than closing. The findings, published in the journal Brain Communications, carry particular urgency given that more than a third of pregnant women worldwide — with rates highest in sub-Saharan Africa and South Asia — have anaemia, typically caused by iron deficiency, prompting researchers to call for routine screening and iron supplementation during pregnancy as a public health priority.