Maternal Obesity during Pregnancy is Associated with Lower Cortical Thickness in the Neonate Brain

Abstract

BACKGROUND AND PURPOSE:Recent studies have suggested that maternal obesity during pregnancy is associated with differences in neurodevelopmental outcomes in children. In this study, we aimed to investigate the relationships between maternal obesity during pregnancy and neonatal brain cortical development.MATERIALS AND METHODS: Forty-four healthy women (28 normal-weight, 16 obese) were prospectively recruited at ,10 weeks' gestation, and their healthy full-term neonates (23 boys, 21 girls) underwent brain MR imaging. All pregnant women had their body composition (fat mass percentage) measured at $12 weeks of pregnancy. All neonates were scanned at $2 weeks of age during natural sleep without sedation, and their 3D T1-weighted images were postprocessed by the new iBEAT2.0 software. Brain MR imaging segmentation and cortical surface reconstruction and parcellation were completed using age-appropriate templates. Mean cortical thickness for 34 regions in each brain hemisphere defined by the UNC Neonatal Cortical Surface Atlas was measured, compared between groups, and correlated with maternal body fat mass percentage, controlled for neonate sex and race, postmenstrual age at MR imaging, maternal age at pregnancy, and the maternal intelligence quotient and education. RESULTS:Neonates born to obese mothers showed significantly lower (P # .05, false discovery rate-corrected) cortical thickness in the left pars opercularis gyrus, left pars triangularis gyrus, and left rostral middle frontal gyrus. Mean cortical thickness in these frontal lobe regions negatively correlated (R ¼ -0.34, P ¼ .04; R ¼ -0.50, P ¼ .001; and R ¼ -0.42, P ¼ .01; respectively) with the maternal body fat mass percentage measured at early pregnancy.CONCLUSIONS: Maternal obesity during pregnancy is associated with lower neonate brain cortical thickness in several frontal lobe regions important for language and executive functions.

Mother’s physical activity during pregnancy and newborn’s brain cortical development

“…All study procedures were approved by the Institutional Review Board at the University of Arkansas for Medical Sciences, and all participants (pregnant women) provided written informed consents for themselves and their newborns to be included in this study. The study cohort is the same as that in a previous study of relationships between pregnant women’s BMI and newborn’s cortical brain development ( Na et al, 2021 ). In this study, we obtained physical activity data throughout pregnancy and performed additional data analysis.…”

“…An MRI examination of the brain during natural sleep without sedation was performed at the Arkansas Children’s Hospital Department of Radiology for each newborn at ∼2 weeks of postnatal age. The MRI data acquisition protocol has been described previously ( Na et al, 2021 ). Specifically, the newborns were fed 15–30 min prior to the scan, swaddled in warm sheets, bundled using an Infant Immobilizer, and transferred to the scanner room after falling asleep.…”

“…No incidental findings needing medical attention were noted. The pre-processing steps of structural MR images for cortical reconstruction were identical as those reported in a recent publication ( Na et al, 2021 ). Specifically, the 3D T1-weighted images were post-processed by the iBEAT (Infant Brain Extraction and Analysis Toolbox) V2.0 software (developed by the Developing Brain Computing lab and Baby Brain Mapping lab at the University of North Carolina at Chapel Hill).…”

“…These sensitivity analyses indicated that the exclusion may be justified. Finally, given the potential interaction between BMI and physical activity in the pregnant women and our previous findings of relationships between mother’s BMI and offspring’s brain development ( Ou et al, 2015 ; Na et al, 2021 ), we also tested the statistical model with and without adding the pregnant women’s BMI as a covariate. All analyses were applied to each hemisphere separately, and effect sizes (rho values) and significance level ( P -values) between variables of interest were calculated.…”

“…No incidental findings needing medical attention were noted. The pre-processing steps of structural MR images for cortical reconstruction were identical as those reported in a recent publication (Na et al, 2021). Specifically, the 3D T1-weighted images were post-processed by the iBEAT (Infant Brain (Li et al, 2014;Sun et al, 2021).…”