Obesity is a global phenomenon with unfavourable clinical and economic outcomes. The prevalence of maternal obesity has risen at similar rates to global obesity and has two distinct population pathways. Firstly, pregnancy has been identified as a risk factor for the development of obesity due to extreme gestation gain and/or prolonged postpartum weight retention. Secondly the number of pre-gravid obese women has increased dramatically over recent years, making this a high-risk medical group. As such, effective interventions are necessary to prevent and reduce the incidence of excessive gestational weight gain and persistent postpartum weight retention, particularly in overweight and obese women. The focus of this review is on the postpartum period, which includes the first twelve months following childbirth. Exercise has many potential benefits for these women, but, despite considerable interest in the effects of physical activity on maternal body mass, few exercise-based randomised controlled trials exist. Two studies have implemented low to moderate intensity walking programmes as weight management interventions, with limited success. Two, more recent studies have used resistance exercises and active videogames to promote weight loss, however while both types of interventions resulted in significant weight loss, these reductions were not significantly different from the corresponding control groups. As such, a proof of principle with regards to exercise and weight retention in overweight and obese women is not available. More investigation is warranted in this important research area and future studies should be based on accessible, progressive, appropriate and effective exercise strategies.