Does stress attenuate motivation for healthful eating in pregnancy and postpartum?

Despite high motivation for healthful eating during pregnancy, maternal diet quality is inadequate. During pregnancy, women may relax effortful control over eating to reduce stress; thus, stress may override motivation to eat healthfully. This secondary analysis of data from the Pregnancy Eating Attributes Study longitudinal cohort investigated associations of motivation for healthful eating and perceived stress with diet quality during pregnancy (n = 365) and postpartum (n = 266), and investigated whether stress modifies associations of motivation with diet quality. Women (Mage = 31.3; gestational age ≤ 12 weeks) were recruited from the Chapel Hill, North Carolina area and completed multiple 24-h diet recalls (once each trimester of pregnancy, and at 4-6 weeks, 6 months, and 1 year postpartum) and validated measures of perceived stress and motivation for healthful eating (autonomous and controlled). Hierarchical multiple regressions tested associations of diet quality (Healthy Eating Index-2015) with stress, motivation, and their interactions. Additionally, themes extracted from previously-analyzed focus groups conducted with a subsample of participants were re-examined for content relevant to stress, motivation, and diet. Pregnancy and postpartum diet quality was positively associated with autonomous motivation, but was unassociated with controlled motivation and stress. Interaction terms did not appreciably improve model fit. Focus group participants described both internal and external forces contributing to their motivation for healthy eating during pregnancy and described the impact of stress on eating behaviors through amplification of food cravings. Future research is needed to identify influences on maternal motivation for healthful eating.