Abstract
BACKGROUND: Maternal health and lifestyle during pregnancy may be critical for the onset and progression of childhood obesity. Prenatal lifestyle interventions have been shown to positively affect maternal behaviors, gestational weight gain, and anthropometric outcomes in infants at birth. The influence of such interventions on child weight or growth beyond birth is unknown. We therefore examined the association between lifestyle interventions during pregnancy and anthropometric outcomes during childhood. METHODS: A systematic literature search was conducted in three electronic databases, two clinical trial registers and further sources, without language or publication status restrictions. Additionally, 110 study authors were contacted to obtain unpublished data. Randomized controlled trials comparing any antenatal lifestyle or behavioral intervention to standard prenatal care, in women of any body mass index (BMI), with offspring anthropometric data at 1 month of age or older, were considered. Two reviewers independently extracted data and assessed the risk of bias using the Cochrane Collaboration's updated tool. Data on weight, length, and BMI, and corresponding z-scores, were stratified into six age ranges and weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated in univariate and multivariate random-effects meta-analytical models. RESULTS: Twenty trials comprising 11,385 women were included in this systematic review, of which 19 were combined in meta-analyses. Overall, lifestyle interventions during pregnancy were not associated with differences in weight, length, BMI, or corresponding z-scores, in children aged 1 month to 7 years (e.g. weight in 5 to 6 month old children, WMD: 0.02 kg; 95% CI: - 0.05 to 0.10 kg, I(2) = 38%; 13 studies, 6667 participants). Findings remained consistent when studies were stratified by maternal baseline BMI or other risk factors, and intervention content and duration. Based on the GRADE criteria, the strength of the body of evidence was considered moderate. CONCLUSION: Prenatal lifestyle interventions were not shown to influence childhood weight or growth. Nevertheless, women should be encouraged to pursue a healthy lifestyle during pregnancy. Further efforts to establish early prevention strategies for childhood obesity are urgently needed. Thus, large, high-quality studies with pre-planned, long-term follow-ups are warranted. TRIAL REGISTRATION: PROSPERO CRD42018118678 .