Associations between low-moderate prenatal alcohol exposure and brain development in childhood

Background The effects of low-moderate prenatal alcohol exposure (PAE) on brain development have been infrequently studied. Aim To compare cortical and white matter structure between children aged 6 to 8 years with low-moderate PAE in trimester 1 only, low-moderate PAE throughout gestation, or no PAE. Methods Women reported quantity and frequency of alcohol consumption before and during pregnancy. Magnetic resonance imaging was undertaken for 143 children aged 6 to 8 years with PAE during trimester 1 only (n = 44), PAE throughout gestation (n = 58), and no PAE (n = 41). T1-weighted images were processed using FreeSurfer, obtaining brain volume, area, and thickness of 34 cortical regions per hemisphere. Fibre density (FD), fibre cross-section (FC) and fibre density and cross-section (FDC) metrics were computed for diffusion images. Brain measures were compared between PAE groups adjusted for age and sex, then additionally for intracranial volume. Results After adjustments, the right caudal anterior cingulate cortex volume (pFDR = 0.045) and area (pFDR = 0.008), and right cingulum tract cross-sectional area (pFWE < 0.05) were smaller in children exposed to alcohol throughout gestation compared with no PAE. Conclusion This study reports a relationship between low-moderate PAE throughout gestation and cingulate cortex and cingulum tract alterations, suggesting a teratogenic vulnerability. Further investigation is warranted.