The Impact of Maternal Omega‐3 Supplementation on Infant Anthropometric Measures and Pregnancy Outcomes: A Systematic Review and Meta‐Analysis

ABSTRACT Purpose Maternal omega‐3 intake during pregnancy may influence infants’ anthropometric measurements and pregnancy outcomes. This study reviewed research articles investigating the effects of omega‐3 supplementation during pregnancy on infants’ anthropometric indices and pregnancy outcomes. Methods A search for studies conducted up to March 2025 was carried out in Medline/PubMed, Web of Science, and Scopus. To assess the risk of bias in the studies, the Cochrane Risk of Bias Assessment tool for randomized trials was utilized. Outcomes were evaluated using odds ratios (OR) or standardized mean differences (SMD) along with 95% confidence intervals (95% CI). The certainty of evidence was evaluated by GRADE. Results This meta‐analysis included a total of 23 studies involving (intervention group=12,341 and control group=12,294 women). The pooled analysis showed that Omega‐3 supplementation was associated with a modest but statistically significant increase in gestational weight gain (SMD: 0.17; 95%CI 0.03–0.29, p = 0.01). The positive effects were also observed on birth sizes, including birth weight (SMD:0.25; 95%CI 0.12–0.38, p < 0.001), birth length (SMD: 0.35; 95%CI 0.16–0.54, p < 0.001), and birth head circumference (SMD: 0.18; 95%CI 0.01–0.35). Sensitivity analysis revealed that, for some outcomes, significance was lost. Moreover, omega‐3 supplementation was linked to reduced odds ratio for preterm birth significantly (OR: 0.83; 95%CI: 0.75–0.93, p = 0.003). Conclusion Omega‐3 supplementation during pregnancy modestly improves maternal weight gain and infant birth size while reducing the risk of preterm birth, supporting its inclusion in maternal nutrition programs. These results reinforce the potential of omega‐3 supplementation as a beneficial intervention to support maternal and neonatal health.