Association between seafood consumption during pregnancy and the risk of adverse birth outcomes, including low birth weight, macrosomia, and preterm birth: a retrospective birth cohort study in Iran

Abstract

Proper nutrition during pregnancy plays a crucial role in maternal and neonatal health. One of the important dietary components due to its rich content of omega-3 fatty acids and other essential nutrients is seafood. However, the precise relationship between seafood consumption and pregnancy outcomes remains a subject of debate. This study aims to investigate the association between seafood consumption during pregnancy and the risk of adverse birth outcomes, including low birth weight, macrosomia, and preterm birth. This retrospective cohort study was conducted on data collected from 752 pregnant women who gave birth between 2017 and 2021 in Semnan Province, Iran. Maternal dietary intake was assessed using a 147-item Food Frequency Questionnaire (FFQ). Information regarding birth outcomes, neonatal weight, and gestational duration was extracted from medical records. Statistical analyses were performed using appropriate tests, such as the Kruskal-Wallis test and the Mann-Whitney U test. The mean age of the mothers was 29.3 ± 4.9 years. The average monthly seafood consumption was 19.6 ± 2.3 g, with fish consumption at 11.2 ± 2.1 g and canned tuna at 8.3 ± 0.8 g per month. The results indicated no significant association between seafood consumption and birth weight ( P = 0.152), preterm birth ( P = 0.075), or hospitalization due to amniotic fluid leakage ( P = 0.89). The mean maternal BMI was 25.5 ± 4.7. No significant association was observed between maternal age and pregnancy outcomes. The findings of this study suggest that seafood consumption and maternal age are not significantly associated with pregnancy outcomes, including birth weight, preterm birth, and hospitalization due to amniotic fluid leakage. Further interventional and clinical trials are necessary to provide stronger evidence regarding the effects of seafood consumption on pregnancy outcomes. Future research could explore the role of biomarkers (such as maternal blood levels of omega-3 fatty acids), thyroid hormones, and inflammation during pregnancy in relation to seafood intake and birth outcomes.

The authors' abstract, as published at the source. BMC Pregnancy and Childbirth, 2026 · DOI ↗