Maternal pre-pregnancy weight status and gestational weight gain in association with child behavior: The mediating role of prenatal systemic inflammation

Background and aims: Maternal pre-pregnancy obesity and excessive gestational weight gain (EGWG) may predispose children to behavioral problems through increased prenatal inflammation. We investigated the association between maternal body mass index (BMI) and gestational weight gain (GWG), and child behavioral problems (primary aim), and the mediating role of prenatal inflammation (secondary aim). Methods: We used self-reported pre-pregnancy BMI and estimated-GWG data (N = 1137) from a longitudinal cohort study. Maternal serum C-reactive protein (CRP) was measured in the 3rd-trimester. Parent-reported Child Behavior Checklist (CBCL) was used to assess child internalizing and externalizing behaviors at 3-years-of-age. We used analysis of covariance (ANCOVA), multiple linear regression, and mediation analyses for data analysis. Results: Maternal obesity (F = 21.98, df 3836), EGWG (F = 6.53, df 2764), and their combination (F = 18.51, df 3764) were associated with the 3rd trimester CRP, but not child behavior in the whole sample. Maternal underweight was associated with withdrawal problems in all children (β = 0.56, 95%CI, 0.11,1.00) and aggressive behaviors in female children (β = 2.59, 95%CI, 0.28,4.91). Obesity had a significant association with externalizing behaviors in female children after controlling for maternal CRP (β = 3.72, 95%CI, 0.12,7.32). Both inadequate and EGWG were associated with somatic complaints in male children (β = 0.50, 95%CI, 0.05,0.95; β = 0.36, 95%CI, 0.01,0.71, respectively). Combined obesity/EGWG was associated with externalizing (β = 6.12, 95%CI, 0.53,11.70) and aggressive (β = 4.23, 95%CI, 0.90,7.56) behaviors in female children. We found no significant effects through CRP. Conclusions: Maternal pre-pregnancy BMI and GWG showed sex-specific associations with child behavioral problems. Prenatal CRP, although increased in obesity and EGWG, did not mediate these associations.