High pre-pregnancy body mass index (ppBMI) has been linked to neurodevelopmental impairments in childhood. However, very few studies have investigated mechanisms in human cohorts.
Among 1361 mother-child pairs in Project Viva, we examined associations of ppBMI categories with the Peabody Picture Vocabulary Test III [PPVT] and Wide Range Assessment of Visual Motor Abilities [WRAVMA] in early childhood (median 3.2y); and with the Kaufman Brief Intelligence test (KBIT) and WRAVMA in mid-childhood (7.7y). We further examined the role of maternal inflammation in these associations using the following measures from the 2nd trimester of pregnancy: plasma C-reactive protein (CRP), dietary inflammatory index (DII), and plasma omega-6 (n-6): n-3 fatty acid ratio.
Children of mothers with prenatal obesity (ppBMI ≥30 kg/m) had WRAVMA scores that were 2.1 points lower (95% CI: -3.9, -0.2) in early childhood than children of normal weight mothers (ppBMI 18.5-<25 kg/m), in a covariate adjusted model. This association was attenuated when we additionally adjusted for maternal CRP (β -1.8 points; 95% CI: -3.8, 0.2) but not for other inflammatory markers. PpBMI was not associated with other cognitive outcomes.
Maternal inflammation may modestly mediate the association between maternal obesity and offspring visual motor abilities.