Peer-reviewed article
Antenatal maternal anaemia and infant brain structure: high-field (3 T) and ultra-low-field (64 mT) MRI findings from South Africa.
Ringshaw JE, Zieff MR, Bourke NJ, Casella C, Bradford LE et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined how maternal anaemia during pregnancy affects infant brain structure in South Africa using two types of MRI scanning. Researchers followed 394 mother-child pairs from pregnancy through the first two years of life, measuring brain development at multiple time points. Infants born to anaemic mothers had smaller brain volumes in key regions, with differences becoming clear around 12 months of age. The findings suggest that maternal anaemia during pregnancy has measurable effects on children's developing brains in infancy.
Key points
- Maternal anaemia in pregnancy was associated with 3.77% smaller intracranial volume and 3.32% smaller putamen volumes in infants
- Brain differences were detectable from around 12 months of age across both high-field and ultra-low-field MRI systems
- Infants showed 4.39% to 6.27% smaller corpus callosum volumes by 24 months when mothers had anaemia during pregnancy
- Postnatal child anaemia and maternal iron deficiency alone were not associated with brain volume differences in this cohort
- This is the first study to detect maternal anaemia's effects on child brain structure as early as infancy
Limitations
The study is observational with some attrition (subsamples ranged from 195 to 341), and does not establish whether these brain structural differences result in functional or developmental problems for children. The mechanisms linking maternal anaemia to altered brain development and the long-term implications for child outcomes remain unclear.
Abstract
With the evolution of ultra-low-field MRI and the recognition of antenatal maternal anaemia as an important driver of altered neurodevelopment in toddlers and children, it is critical to determine whether these effects are detectable at ultra-low-field (64 mT) in infancy. The aim of this study was to assess the impact of antenatal maternal anaemia on infant brain structure across the first 2 years of life, using high-field (3 T) and ultra-low-field (64 mT) MRI. This neuroimaging substudy was embedded within Khula, an observational population-based birth cohort in South Africa. Pregnant women were enrolled antenatally and postnatally. Mother-child dyads (n = 394) were followed prospectively with a subsample attending neuroimaging at ∼3, 6, 12, 18 and 24 months of age. Anaemia was classified using World Health Organization thresholds, and neuroimaging data were processed using MiniMORPH. Linear mixed-effects models were used to investigate associations between antenatal maternal anaemia status and absolute regional infant brain volumes using high-field and ultra-low-field MRI. In repeated measures high-field (n = 195) and ultra-low-field (n = 341) infant neuroimaging subsamples, the prevalence of antenatal maternal anaemia was 28.24% (37/131) and 29.76% (61/205), respectively. Maternal anaemia in pregnancy was associated with altered child brain structure across both MRI systems, with group differences becoming detectable at ∼12 months. In the ultra-low-field subsample, infants born to anaemic mothers had 3.77% smaller intracranial volume (β = -0.24, P = 0.004) and 3.32% smaller putamen volumes (β = -0.18, P = 0.040) across the first 2 years of life. The interaction between antenatal maternal anaemia and age was significant for the caudate nucleus (β = -0.13, P = 0.038) and corpus callosum (β = -0.15, P = 0.007). Antenatal maternal anaemia was associated with 3.70% and 4.29% smaller caudate nucleus volumes at 18 and 24 months of age, respectively. Similarly, infants born to anaemic mothers had 4.39% smaller corpus callosum volumes by 12 months and 6.27% smaller corpus callosum volumes by 24 months. Postnatal child anaemia and antenatal maternal iron deficiency status were not associated with total or regional child brain volumes in the ultra-low-field subsample from this cohort. Maternal anaemia remained a robust predictor of volume differences in sensitivity analyses. This study is the first to demonstrate that the impact of maternal anaemia in pregnancy on child brain structure is detectable as early as infancy. The implications of this research are 2-fold: (i) informing the feasibility of ultra-low-field MRI in low- and middle-income countries and (ii) the timing and optimization of targeted recommendations for anaemia management in practice and policy.