Demographic and health characteristics associated with fish and n-3 fatty acid supplement intake during pregnancy: results from pregnancy cohorts in the ECHO program

Objective: Omega-3 (n-3) fatty acid consumption during pregnancy is recommended for optimal pregnancy outcomes and offspring health. We examined characteristics associated with self-reported fish or omega-3 supplement intake. Design: Pooled pregnancy cohort studies. Setting: Cohorts participating in the Environmental influences on Child Health Outcomes (ECHO) consortium with births from 1999-2020. Participants: A total of 10,800 pregnant people in 23 cohorts with food frequency data on fish consumption; 12,646 from 35 cohorts with information on supplement use. Results: Overall, 24.6% reported consuming fish never or less than once per month, 40.1% less than once a week, 22.1% 1-2 times per week, and 13.2% more than twice per week. The relative risk (RR) of ever (vs. never) consuming fish was higher in participants who were older (1.14, 95% CI: 1.10, 1.18 for 35-40 vs. <29 years), were other than non-Hispanic White (1.13, 95% CI: 1.08, 1.18 for non-Hispanic Black; 1.05, 95% CI: 1.01, 1.10 for non-Hispanic Asian; 1.06, 95% CI: 1.02, 1.10 for Hispanic), or used tobacco (1.04, 95% CI: 1.01, 1.08). The RR was lower in those with overweight vs. healthy weight (0.97, 95% CI: 0.95, 1.0). Only 16.2% reported omega-3 supplement use, which was more common among individuals with a higher age and education, a lower BMI, and fish consumption (RR 1.5, 95% CI: 1.23, 1.82 for twice-weekly vs. never). Conclusions: One-quarter of participants in this large nationwide dataset rarely or never consumed fish during pregnancy, and omega-3 supplement use was uncommon, even among those who did not consume fish.