Background/aims Being born small-for-gestational-age (SGA), a proxy for fetal growth restriction (FGR) has been related to poor school performance, lower academic achievement and cognitive problems. The aim of this study was to investigate whether young adults born SGA at term had reduced brain volumes, cortical surface area and/or cortical thickness, and whether brain morphometry measures were related to cognitive functioning.
Methods In this population-based follow-up study at age 20, 58 term-born SGA (birthweight < 10 th centile, mean: 2915 g) and 81 non-SGA controls (birthweight >10 th centile, mean: 3707 g) were included. MRI-examinations at 1.5 T were obtained in 47 SGA and 61 control subjects. Image analysis was performed by the FreeSurfer, version 5.1. IQ was assessed by Wechsler Adult Intelligence Scale 3rd edition (WAIS-III).
Results Total brain volume was smaller in the SGA than in the control group (-5.6%; p < 0.001). This reduction included most structures, but relative volumes were the same. Cortical surface area was significantly reduced in the SGA group compared with controls in multiple regions across the cerebral cortex, especially in the frontal, parietal and temporal lobes compared with controls (Figure). The reduction in surface area in the SGA group was most pronounced in the anterior cingulate gyri bilaterally. No associations were found between brain measures and IQ measures in either group.