Associations between maternal pre-pregnancy BMI and mean diffusivity of the hippocampus and amygdala in infants.

Abstract

Maternal pre-pregnancy obesity may negatively affect offspring outcomes, including neurodevelopment. This study examined the relationship between maternal pre-pregnancy body mass index (MBMI) and the microstructure of the hippocampus and amygdala in neonates. Diffusion tensor imaging was used to assess mean diffusivity (MD) in these brain regions in 122 infants (mean gestational age: 39.9 weeks, mean age at scan: 24.8 days) from the FinnBrain Birth Cohort Study ( www.finnbrain.fi ). Linear regression was applied to explore associations between MBMI and MD at the regional level, while non-parametric permutation analysis was used for voxelwise investigations. A positive association was found between MBMI and hippocampal MD, particularly in the right hippocampus. Voxelwise analyses showed stronger associations in distinct areas: posterior for the right hippocampus and anterior for the left. No significant association was found between MBMI and amygdala MD. These findings suggest that in utero exposure to high MBMI may influence hippocampal microstructure in infants, underscoring the need for further research on the intergenerational effects of maternal obesity on early brain development.