The Joint Impact of Maternal Pregnancy Diet and Postnatal Stimulation and Support on Executive Function and Behaviour in 3-4 Year-Olds
Introduction: Optimal maternal nutrition during pregnancy is associated with superior cognitive and behavioural development in children. However, it is not known if it can protect against sub-optimal postnatal exposures like reduced availability of stimulation and support in the home.
Methods: 800 participants aged 3-4 years enrolled in the Maternal-Infant Research on Environmental Chemicals (MIREC). Maternal diet quality during pregnancy was assessed using a 46-item food frequency questionnaire. The amount of stimulation and support available in the home environment was assessed when children were aged 3-4 years old using the Home Observation for Measurement of the Environment (HOME). Important aspects of executive function including planning and working memory were assessed at 3-4 years using the Behaviour Rating Inventory of Executive Functioning-Preschool Edition (BRIEF-P), and child behaviour were maternally reported using the Behaviour Assessment System for Children- 3rd Edition (BASC-3). Linear regression analyses adjusted for maternal years of education, depression at 6 months postpartum, pre-pregnancy BMI, and maternal prenatal smoking.
Results: Better overall maternal diet quality during pregnancy was associated with better working memory (B=0.73, p=0.001) and planning (B=0.38, p=0.006) on the BRIEF-P, and higher adaptability (B=-0.90, p= 0.030) on the BASC-3 when HOME scores were lower.
Conclusions: In a large longitudinal Canadian cohort, better maternal diet quality during pregnancy was linked to higher scores on the BRIEF-P and BASC-3 scales when children were raised in less than optimal home environments marked by lower stimulation and support. These results suggest that optimal diet quality during pregnancy could help protect against the adverse effects on cognition and behaviour of a less than optimal home environment postnatally. Pregnancy nutrition could represent a significant component of the next successfully implemented research-enabled public health strategy: optimizing child neurodevelopment.