Maternal pre-pregnancy body mass index, child temperament, and childhood obesity risk

Abstract

Abstract Background Maternal obesity prior to and during pregnancy is related to increased risk of obesity in the child. This risk may be in part mediated by altered child temperament, which can affect mother-child interactions including feeding and soothing behaviors that affect obesity risk. Our objective was to examine the association between maternal pre-pregnancy BMI and child zBMI, and determine if child temperament, specifically positive affectivity/surgency, mediates this association. Methods Using conditional process modeling, we analyzed prospectively collected data from 408 mother-child dyads enrolled in the Alberta Pregnancy Outcomes and Nutrition (APrON) study. Child temperament was assessed by the Child Behaviour Questionnaire (CBQ) Very Short Form at 3 years of age and zBMI was calculated from in-clinic height and weight measurements at 4 years of age. Results The indirect effect of pre-pregnancy BMI on child zBMI through Surgency scores as a mediator was significant after controlling for maternal gestational weight gain, socioeconomic status, maternal anxiety and depression, and child cognitive and emotional support (β = 0.003, 95% CI [0.0001, 0.008]). Overall, maternal pre-pregnancy BMI and child zBMI were directly associated and there was an indirect association through child temperament, whereby increased Surgency was associated with higher zBMI scores. Conclusions Child zBMI score is associated with maternal pre-pregnancy BMI, and this relationship is mediated by the temperament of the child, specifically Surgency.