Can gestational weight gain be modified by increasing physical activity and diet counseling? A meta-analysis of interventional trials.

BACKGROUND Excessive gestational weight gain (GWG) increases the risk of a number of adverse pregnancy outcomes and was recently identified as a potential risk factor for childhood obesity. It is therefore of interest whether GWG can be modified by an intervention combining dietary counseling and physical activity. OBJECTIVE The objective was to review published data on interventions to reduce GWG by modulating diet and physical activity during pregnancy. DESIGN We systematically reviewed 4 databases and bibliographies of various publications supplemented by a hand-search for relevant articles published in English or German and performed a meta-analysis to quantify the effect estimate by a random-effects model. RESULTS Four randomized controlled trials and 5 nonrandomized trials with a total of 1549 women enrolled were identified as being relevant. Meta-analyses of all 9 trials indicated a lower GWG in the intervention groups, with a standardized mean difference of -0.22 units (95% CI: -0.38, -0.05 units). We observed no indication for publication bias. CONCLUSIONS Interventions based on physical activity and dietary counseling, usually combined with supplementary weight monitoring, appear to be successful in reducing GWG. The results are of particular interest with respect to the objective of preventing excessive GWG.