Maternal Fish Intake in the Year Prior to Conception and Birth Defects, National Birth Defects Prevention Study, 1997–2011

BACKGROUND: Epidemiologic data on the association between maternal fish intake and birth defects are sparse. Our objective was to assess associations between maternal fish intake and 52 different birth defects, most of which have not been assessed previously. METHODS: Using logistic regression, data was analyzed for 29,242 mothers of infants with birth defects and 10,973 mothers of control infants who participated in the National Birth Defects Prevention Study (NBDPS) and delivered between 1997 and 2011. We focused on associations between mothers who reported high fish intake of 2 or more servings of fish per week for the year prior to conception versus those who reported little or no fish intake and 52 birth defects. Each birth defect was analyzed separately. RESULTS: Among control mothers, 13.9% reported high fish intake and 31.3% reported eating very little or no fish. High fish intake was associated with lower odds of 9 birth defects (isolated heterotaxia, double outlet right ventricle transposition of the great arteries, total anomalous pulmonary venous return, Dandy Walker syndrome, holoprosencephaly, choanal atresia, cleft palate, craniosynostosis, and gastroschisis) with adjusted odds ratios (aORs) ranging from 0.32 to 0.83. An elevated association with high fish intake was observed for one birth defect (tricuspid atresia, aOR = 1.76; 95% CI 1.07, 2.89). CONCLUSION: Based on our findings, consumption of 2 or more servings of fish per week may help to prevent certain types of birth defects. This conclusion is similar to the existing FDA (Food and Drug Administration) recommendation that women who are or can become pregnant should consume 2-3 servings of low mercury seafood per week. A large majority of pregnant women in this US (United States) based study did not meet the FDA recommendations for fish intake, suggesting that many of them may have benefited from increasing their consumption of seafood.