Periconceptional seafood intake and pregnancy complications.

OBJECTIVE: To investigate associations of maternal periconceptional shellfish, lean fish and fatty fish intake with risk of pregnancy complications. DESIGN: In this prospective cohort study, we collected information on intake of seafood subtypes using FFQ. We categorized seafood intake into frequencies of 1 servings/week. We ascertained gestational hypertension, pre-eclampsia, gestational diabetes and preterm birth diagnoses from medical records. Using generalized linear models with a log link, the Poisson family and robust standard errors, we estimated risk ratios and 95 % confidence intervals across seafood intake categories. SETTING: The Omega study, a study of risk factors for pregnancy complications among women recruited from prenatal clinics in Washington State, USA, 1996-2008. SUBJECTS: The current study included 3279 participants from the Omega study. RESULTS: Median (interquartile range) shellfish, lean fish and fatty fish intake was 0·3 (0-0·9), 0·5 (0-1·0) and 0·5 (0·1-1·0) servings/week, respectively. Lean fish intake of >1 servings/week (v. <0·2 servings/month) was associated with a 1·55-fold higher risk of preterm birth (95 % CI 1·04, 2·30) and was not associated with the other pregnancy complications. Higher intake of seafood (total or other subtypes) was not associated with pregnancy complications (separately or combined). CONCLUSIONS: Higher intake of lean fish, but not fatty fish or shellfish, was associated with a higher risk of preterm birth; these findings may have significance for preterm birth prevention. Studies of mechanisms and potential contributing factors (including seafood preparation and nutrient/contaminant content) are warranted.