Fish consumption among pregnant women in London, Ontario: associations with socio-demographic and health and lifestyle factors.

BACKGROUND Intake of fish and omega-3 fatty acids is inversely related to adverse health outcomes; however, these relationships may be confounded by socio-economic status and health behaviours. This study's purpose was to describe the socio-demographic, health and lifestyle correlates of fish consumption among pregnant women. METHODS Pregnant women (n=2394) completed a telephone interview between 10-22 weeks' gestation (London, Ontario, 2002-5) containing questions on socio-demographic, health and lifestyle variables; dietary intake was measured using a 106-item validated food-frequency questionnaire. Unadjusted and adjusted risk ratios were obtained using a modified Poisson regression model. RESULTS Infrequent fish consumption, <1/week, was reported by 32% of women. After adjusting for age and education, infrequent fish consumption was associated with education <high school (RR=1.60; 95% CI 1.30-1.96); age (< or =21: RR=1.53; 95% CI 1.17-2.02; 22-25: RR=1.41; 95% CI 1.11-1.78; and 26-34: RR=1.39; 95% CI 1.15-1.69); current smoking status (RR=1.20; 95% CI 1.00-1.43); average exercise duration <30 minutes (never: RR=1.22; 95% CI 1.06-1.39 and 1-29 minutes: RR=1.25; 95% CI 1.08-1.45); obesity (RR=1.19; 95% CI 1.01-1.41); and not meeting Canadian dietary guidelines for consumption of vegetables and fruit (RR=1.60; 95% CI 1.42-1.79), milk products (RR=1.19; 95% CI 1.05-1.36), and meat and alternatives (RR=1.89; 95% CI 1.69-2.12). Compared to frequent fish consumers, infrequent fish consumers were less likely to be moderate drinkers prior to pregnancy (RR=0.85; 95% CI 0.75-0.96). CONCLUSION Infrequent fish consumption was associated with lower socio-economic status and variables indicative of a less healthy lifestyle; these variables may act as confounders in studies evaluating fish consumption and health outcomes.