STRUCTURAL ASSESSMENT OF THE FETAL BRAIN IN LATE-ONSET FETAL GROWTH RESTRICTION USING MAGNETIC RESONANCE IMAGING

Objective: To assess the volumes of fetal anatomical structures using magnetic resonance imaging (MRI) in pregnant women with late-onset fetal growth restriction (FGR) and small-for-gestational-age (SGA) fetuses. Materials and methods: This prospective cohort study included 15 pregnant women with late-onset FGR and 15 pregnant women with SGA who underwent MRI. The control group consisted of nine pregnant women with appropriate-for-gestational-age fetuses. Using manual selection of the regions of interest, the volumes of the supratentorial brain and cerebellum were measured, and their ratios were calculated. Quantitative measurements of all the brain structures were converted to percentile values. Results: The percentile values of supratentorial brain and cerebellum volumes were significantly smaller in the late-onset FGR group (p=0.004 and p<0.001, respectively). There were no statistically significant differences in the volume of the brain structures in the SGA group. Conclusion: Fetuses with late-onset fetal growth restriction have reduced supratentorial brain and cerebellar volumes, as assessed by MRI, compared with controls. Placental insufficiency in late-onset FGR has a greater effect on brain volume than on birth weight. Further studies are needed to clarify the areas of interest in the brain and to determine their association with the severity and likelihood of reversibility of neurological deficits in newborns and infants with late-onset fetal growth restriction. © 2025 Elsevier B.V., All rights reserved.