Higher fish consumption in pregnancy may confer protection against the harmful effect of prenatal exposure to fine particulate matter.

BACKGROUND/AIM The objective of this study was to assess a hypothesized beneficial effect of fish consumption during the last trimester of pregnancy on adverse birth outcomes resulting from prenatal exposure to fine air particulate matter. METHODS The cohort consisted of 481 nonsmoking women with singleton pregnancies, of 18-35 years of age, who gave birth at term. All recruited women were asked about their usual diet over the period of pregnancy. Measurements of particulate matter less than 2.5 mum in size (PM(2.5)) were carried out by personal air monitoring over 48 h during the second trimester of pregnancy. The effect of PM(2.5) and fish intake during gestation on the birth weight of the babies was estimated from multivariable linear regression models, which beside the main independent variables considered a set of potential confounding factors such as the size of the mother (height, prepregnancy weight), maternal education, parity, the gender of the child, gestational age and the season of birth. RESULTS The study showed that the adjusted birth weight was significantly lower in newborns whose mothers were exposed to particulate matter greater than 46.3 microg/m3 (beta coefficient = -97.02, p = 0.032). Regression analysis stratified by the level of maternal fish consumption (in tertiles) showed that the deficit in birth weight amounted to 133.26 g (p = 0.052) in newborns whose mothers reported low fish intake (<91 g/week). The birth weight deficit in newborns whose mothers reported medium (91-205 g/week) or higher fish intake (>205 g/week) was insignificant. The interaction term between PM(2.5) and fish intake levels was also insignificant (beta = -107,35, p = 0.215). Neither gestational age nor birth weight correlated with maternal fish consumption. CONCLUSIONS The results suggest that a higher consumption of fish by women during pregnancy may reduce the risk of adverse effects of prenatal exposure to toxicants and highlight the fact that a full assessment of adverse birth outcomes resulting from prenatal exposure to ambient hazards should consider maternal nutrition during pregnancy.