OBJECTIVETo evaluate systematically the effect of n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) supplementation of pregnant women on head circumference of newborn infants.

METHODSA thorough literature search was done for full texts which studied the effect of n-3 LC-PUFA supplementation of pregnant women on head circumference of newborn infants among PubMed, Cochrane Library, Chinese periodical full text database and Wanfang database using the mesh terms as n-3, long chain polyunsaturated fatty acids, DHA, EPA, docosahexaenoic acid, eicosapentaenoic acid, fish oil, pregnancy, infant. Only randomized controlled trials were chosen for analysis. A total of 74 relevant articles were selected. RevMan 5.0 software was used to perform the Meta analysis on those valid studies. Weighted mean difference was calculated with inverse variance method. The sensitivity analysis was also performed.

RESULTSEight articles met the inclusion criteria, among which 6 literatures were from developing countries and the other 2 from developed countries. All of them were written in English. These studies were reported from 2001 to 2011. Intervention group included 871 objects with n-3 LC-PUFA supplementation, whereas control group included 894 objects with placebo or no supplementation. Supplementation was associated with significantly greater head circumference of the infants in the intervention group than that of the control group (weighted mean difference was 0.17 cm, 95%confidence interval (CI) was 0.01 - 0.32 cm, P < 0.05). But the difference was no long significant according to the sensitivity analysis (weighted mean difference was 0.16 cm, 95%CI was -0.01 - 0.34 cm, P = 0.07). The funnel plot was symmetrical, indicating there was no publication bias between the eight studies.

CONCLUSIONIt can't be confirmed whether supplementation with n-3 LC-PUFA of pregnant women can increase the infants' head circumference at birth from present data acquired.