Prenatal long-chain polyunsaturated fatty acid status: the importance of a balanced intake of docosahexaenoic acid and arachidonic acid

This review addresses the effect of prenatal long-chain polyunsaturated fatty acid (LCPUFA) status on neuro-developmental outcome. It focuses on the major LPCUFA doxosahexaenoic acid (DNA; 22:6 omega 3) and arachidonic acid (AA; 20:4 omega 6). Due to enzymatic competition high DHA intake results in lower tissue levels of AA. LCPUFA accumulation in the brain starts early and increases during the third trimester. Initially brain AA-accretion exceeds DHA-accretion; after term age DHA-accretion surpasses AA-accretion. Animal studies indicated that early omega 3-depletion results in poorer developmental outcome. They also showed that early omega 3-supplementation had no effect on cognitive outcome, promotes visual development and impairs auditory and motor development. Only limited human data are available. Correlational studies suggest that neonatal AA status shows a positive relation with early neurodevelopmental outcome and that neonatal DHA status also might be correlated with improved outcome beyond infancy. Results of human intervention studies are equivocal: most studies were unable to demonstrate a positive effect of prenatal w3-supplementation. It is concluded that only limited evidence exists to support the notion that prenatal w3-supplementation favours developmental outcome. Caution is warranted for an unbalanced high DHA intake during the first two trimesters of pregnancy, i.e., DHA without additional AA supplementation.