Associations between maternal adiposity during pregnancy and neonatal brain cortical development

Previous studies have suggested that obesity during pregnancy is associated with changes in child neurodevelopmental outcomes, indicating in utero effects of maternal obesity on offspring brain development.

This study aims to evaluate whether there are associations between maternal body fat mass percentage (a direct measure of adiposity) at different stages of pregnancy and neonatal cortical brain development.

169 mother/newborn dyads (79 boys and 90 girls) were included in this longitudinal and prospective study. Maternal fat mass percentage was assessed using air displacement plethysmography methodology at 12 and 36 weeks of pregnancy. At ∼2 weeks of postnatal age, the neonates underwent a brain MRI during natural sleep without sedation using high-resolution 3D T1- and T2-weighted imaging. Multiple linear regression models, controlling for appropriate covariates, were used to evaluate associations between maternal fat mass percentage and neonatal cortical features (volume, thickness, and surface area), as well as to test for interaction effects between neonatal sex and maternal fat mass percentage on these outcomes.

Maternal fat mass percentage at 12 weeks of pregnancy negatively associated with neonatal cortical volume of left entorhinal cortex (ꞵ = -1.36, t = -3.53, P = 0.04), and left parahippocampal gyrus (ꞵ = -1.50, t = -3.31, P = 0.04); maternal fat mass percentage at 36 weeks of pregnancy negatively associated with neonatal cortical volume of left entorhinal cortex (ꞵ = -1.76, t = -3.25, P = 0.04), left parahippocampal gyrus (ꞵ = -2.26, t = -3.53, P = 0.04), and right temporal pole (ꞵ = -2.24, t = -3.19, P = 0.04). Sex interaction with maternal fat mass percentage at 12 weeks significantly associated with cortical volume in left pars triangularis (ꞵ = -8.28, t = -3.46, P = 0.05).

Significant relationships were identified between maternal body fat mass percentage during pregnancy and neonatal cortical volume, suggesting potential in utero and sex-specific impacts of increased maternal adiposity on offspring brain development.