• n-3 Polyunsaturated fatty acids;
  • cigarette smoking;
  • red blood cells;
  • placental weight;
  • pregnancy outcome


Objective. To investigate pregnancy outcome in relation to red blood cell (RBC) level of long-chain n-3 polyunsaturated fatty acids (PUFA) in the first trimester of pregnancy and the influence of lifestyle factors on the RBC level of long-chain n-3 PUFA. Design and setting. Observational study in a community with traditional fish and cod liver oil consumption. Population. Seventy-seven healthy pregnant women. Methods. The PUFA composition of RBC was measured in the 11th to 15th week of pregnancy. The women answered food frequency and lifestyle questionnaires. Information on pregnancy outcome was collected from birth records. Main outcome measures. Placental weight, long-chain n-3 PUFA in diet and RBC, smoking. Results. Of all the pregnancy outcome variables tested, placental weight was the only one associated with long-chain n-3 PUFA in RBC. Inverse association was found between the proportion of long-chain n-3 PUFA in RBC and placental weight, adjusted for birthweight (p = 0.035). The proportion of long-chain n-3 PUFA in RBC was positively related to long-chain n-3 PUFA intake (p<0.001) and negatively related to smoking (p = 0.011). Conclusion. The human fetus relies on maternal supply and placental delivery of long-chain n-3 PUFA for optimal development and function, particularly of the central nervous system. Given the importance of dietary n-3 PUFA during pregnancy, further studies are warranted to investigate the relationship between placental weight, maternal long-chain n-3 PUFA status and smoking.