Maternal Cod Intake during Pregnancy and Infant Development in the First Year of Life: Secondary Analyses from a Randomized Controlled Trial

Abstract

Background: Maternal seafood intake during pregnancy is associated with child neurodevelopment. No randomized controlled trials (RCTs) have examined the effect of maternal lean fish consumption during pregnancy on child neurodevelopment.

Objectives: The objective of the study was to examine the effect of increased maternal cod intake during pregnancy on infant general and socio-emotional development in the first year of life, and whether any effects observed were mediated by maternal iodine status.

Methods: In an RCT, 133 pregnant women (≤19 weeks of gestation) were randomly assigned to receive 200 g cod fillet twice weekly (intervention) or to continue with their habitual diet (control) for 16 wk. The mothers completed the developmental screening questionnaires Ages and Stages Questionnaire, 2nd edition (ASQ-2) and Ages and Stages Questionnaire: Social-Emotional (ASQ:SE) when the infants were 3, 6, and 11 mo old. We compared scores between groups using linear mixed-effects models and examined whether iodine status postintervention mediated the effect on child development.

Results: We found no difference between infants in the intervention and control groups on total ASQ-2 scores (P = 0.633), but a difference on the ASQ:SE scores in favor of the intervention group (20.9 and 20.5 in the intervention group and 26.1 and 26.8 in the control group for 3 and 6 mo, respectively; P = 0.020). There was no difference in change of the scores between the groups over time (P = 0.946). The effect of group on the total ASQ:SE scores was not mediated via maternal urinary iodine concentration postintervention (β = -1.03, SE = 0.68, P = 0.126).

Conclusions: Our results provide no evidence for an effect of increased cod intake during pregnancy on general child development in the first year of life, but there was a positive effect on socio-emotional problems. More studies are needed to define the role of fish consumption during pregnancy and the effects on child neurodevelopment.This trial was registered at clinicaltrials.gov as NCT02610959.

Keywords: Ages and Stages Questionnaire; child development; iodine; maternal fish consumption; pregnancy.

© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.