Effects of n-3 long-chain polyunsaturated fatty acid supplementation during pregnancy and/or lactation on neurodevelopment and visual function in children: a systematic review of randomized controlled trials.

OBJECTIVE

To systematically evaluate the effects of n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) supplementation of pregnant and/or lactating women on the neurodevelopment and visual function of their children.

METHODS

Systematic review. Randomized controlled trials (RCTs) comparing n-3 LCPUFA maternal supplementation were identified through electronic databases (MEDLINE, EMBASE, the Cochrane Library) and the references of reviewed articles.

RESULTS

Overall, 13 publications, some with important methodological limitations, were included. With regard to supplementation during pregnancy, among 3 RCTs that evaluated this intervention, 1 RCT (n = 72) showed significantly better eye and hand coordination assessed with the Griffiths Mental Development Scales at 30 months of age. Another RCT (n = 29) demonstrated an effect of n-3 LCPUFA supplementation on the cloth step of intentional solutions of the 2-step problem-solving test. No other effects were demonstrated. There was no consistent effect of n-3 LCPUFA supplementation during pregnancy on the children's visual acuity. With regard to supplementation during lactation, among 3 RCTs that assessed this intervention, 1 RCT (n =133) showed significant improvement on the Bayley Psychomotor Development Index in 30-month-old children; however, there was no influence of such supplementation on the results of different tests performed in the same group of children or in others. There was no consistent effect of n-3 LCPUFA supplementation during lactation on the children's visual function. Supplementation during pregnancy and lactation (3 RCTs) did not affect child neurodevelopment assessed up to 7 years of age.

CONCLUSION

Evidence from RCTs does not demonstrate a clear and consistent benefit of n-3 LCPUFA supplementation during pregnancy and/or lactation on child neurodevelopment and visual acuity. These results should be interpreted with caution due to methodological limitations of the included studies.