The effectiveness of ω-3 polyunsaturated fatty acid interventions during pregnancy on obesity measures in the offspring: an up-to-date systematic review and meta-analysis

Abstract

Background: The potential role of ω-3 long chain polyunsaturated fatty acid (LCPUFA) supplementation during pregnancy on subsequent risk of obesity outcomes in the offspring is not clear and there is a need to synthesise this evidence.

Objective: A systematic review and meta-analysis of randomised controlled trials (RCTs), including the most recent studies, was conducted to assess the effectiveness of ω-3 LCPUFA interventions during pregnancy on obesity measures, e.g. BMI, body weight, fat mass in offspring.

Methods: Included RCTs had a minimum of 1-month follow-up post-partum. The search included CENTRAL, MEDLINE, SCOPUS, WHO's International Clinical Trials Reg., E-theses and Web of Science databases. Study quality was evaluated using the Cochrane Collaboration's risk of bias tool.

Results: Eleven RCTs, from ten unique trials, (3644 children) examined the effectiveness of ω-3 LCPUFA maternal supplementation during pregnancy on the development of obesity outcomes in offspring. There were heterogeneities between the trials in terms of their sample, type and duration of intervention and follow-up. Pooled estimates did not show an association between prenatal intake of fatty acids and obesity measures in offspring.

Conclusion: These results indicate that maternal supplementation with ω-3 LCPUFA during pregnancy does not have a beneficial effect on obesity risk. Due to the high heterogeneity between studies along with small sample sizes and high rates of attrition, the effects of ω-3 LCPUFA supplementation during pregnancy for prevention of childhood obesity in the long-term remains unclear. Large high-quality RCTs are needed that are designed specifically to examine the effect of prenatal intake of fatty acids for prevention of childhood obesity. There is also a need to determine specific sub-groups in the population that might get a greater benefit and whether different ω-3 LCPUFA, i.e. eicosapentaenoic (EPA) vs. docosahexanoic (DHA) acids might potentially have different effects.

Keywords: Adiposity; Body composition; Childhood obesity; Fatty acids; Fish oil; Growth; Infant’s growth; Meta-analysis; N-3 LCPUFA; Obesity; Systematic review.

Fig. 1

Study flow diagram, following preferred reporting items for systematic reviews and meta-analyses (PRISMA) criteria

Fig. 2

Risk of bias assessment figure in the included trials

Fig. 3

Forest plot for prenatal intake of fatty acid vs. placebo for BMI

Fig. 4

Forest plot for prenatal intake of fatty acid vs. placebo for BMI-Z

Fig. 5

Forest plot for prenatal intake of fatty acid vs. placebo for sum of SFT

Fig. 6

Forest plot for prenatal intake of fatty acid vs. placebo for body fat (%)

Fig. 7

Forest plot for prenatal intake of fatty acid vs. placebo for fat mass (kg)

Fig. 8

Forest plot for prenatal intake of fatty acid vs. placebo for weight

Fig. 9

Forest plot for prenatal intake of fatty acid vs. placebo for height