“Is fish consumption during pregnancy beneficial for children?”


The fetal and infant period is a particular critical developmental period, and there is evidence that has suggested that nutritional perturbations during this period have long-term effects on offspring health.

Fish consumption is beneficial for human health due to its nutritional content (fatty acids, protein, selenium, iodine, and vitamin D). However, pollution of rivers, lakes, and oceans has led to the accumulation of certain pollutants, such as heavy metals (i.e. mercury), polychlorinated biphenyls (PCB), and dioxin in fish. Therefore its consumption can serve as a source of human exposure to environmental pollutants.

It is clear that there are a variety of fish and seafood, particularly large predator fish, such as sharks, swordfish, king mackerel, and tilefish that contain high levels of pollutants, especially mercury. However, previous studies showed inconsistent results whether fish consumption has adverse health effects on pregnancy and the developing fetus. Understanding clearly the potential benefits and hazards related to fish and seafood consumption is therefore extremely important.

Dr. Leventakou and colleagues examined whether regular fish consumption amongst pregnant European women had an effect on the developing fetus. Particularly, they assessed the effects on fetal growth and the duration of gestation.

In this study, more than 150.000 mother–newborn pairs from 29 European birth cohort studies were included, also those from the INMA project. The investigators measured the weekly fish consumption and the length of the pregnancy and the birth weight of the newborn as indicators of development. They found that fish consumption increased birth weight, meaning that newborns of women who had been consuming fish more than once a week had an increased weight at birth as compared to the newborns whose mother consumed fish less than once a week. This positive effect was even more evident among mothers who had been smoking during pregnancy, or who were overweight or obese during this period. In addition, they found that women who had been consuming fish more than once a week during pregnancy had a lower risk of having preterm delivery.

In conclusion, the investigators highlighted that moderate fish consumption during pregnancy could be beneficial for the mother and the developing fetus. However, the long-term effects of fish consumption during pregnancy, principally on the development of the cognitive function of the newborn, require further examination. The investigators also emphasize that pregnant women should favor the consumption of a variety of fish and seafood that is low in pollutants, such as mercury and high in omega 3 fatty acids.

Reference: Leventakou V, et al. Fish intake during pregnancy, fetal growth, and gestational length in 19 European birth cohort studies. Am J Clin Nutr. 2014 Mar;99(3):506-16.