Exercise interventions for weight management during pregnancy and up to 1 year postpartum among normal weight, overweight and obese women: a systematic review and meta-analysis.

BACKGROUND: The prevalence of excessive gestation weight gain, extended postpartum weight retention and pregravid obese women is increasing and is associated with numerous adverse health outcomes. OBJECTIVE: To review the evidence from studies employing exercise-only interventions for weight management among pregnant and postpartum women. SEARCH STRATEGY: Ten databases were searched for randomised controlled trials conducted during pregnancy or within the 12 months following childbirth and published between 1990 and 2013. SELECTION CRITERIA: There were no restrictions to the type, frequency, duration or intensity of exercise intervention. Interventions not specifically designed to target weight were excluded. The outcomes were a change in body weight (kg) or body mass index (BMI; kg/m(2)). DATA COLLECTION AND ANALYSIS: All data were continuous and were reported as weighted mean differences (WMD), with 95% CIs. Data were analysed with a fixed-effect model and heterogeneity was determined using the I(2) statistic. RESULTS: Five studies were included in this review. Exercise significantly reduced gestational weight gain (WMD=-2.22 kg, CI -3.14 to -1.3, p≤0.00001) and had no significant effect on postpartum weight loss (WMD=-1.74 kg, CI -3.59 to 0.10, p=0.06) or BMI during pregnancy (WMD=-2.8 kg/m(2), CI -5.60 to 0.00, p=0.05) or postpartum (WMD=-0.54 kg/m(2), CI -1.17 to 0.08, p=0.09). CONCLUSIONS: There is currently limited evidence to suggest that exercise can be used to limit maternal gestational weight gain.