Retention of weight gained in pregnancy contributes to the development of overweight and obesity in middle age, now at epidemic proportions in America. While interventions to reduce weight retention specifically targeting the postpartum period have been few, interventions that promote modest weight loss starting in early postpartum are safe and could be efficacious, particularly for women who were overweight prior to pregnancy. Moreover, postpartum-related changes in cognitive factors (risk perceptions), behavioral factors (physical activity, diet), self concept (self-esteem) and social role (work, food preparation, child care) may make this time a "teachable moment" that could be capitalized upon by formal interventions. Interventions could leverage natural weight changes to encourage adoption of a healthy diet and increase physical activity, which together could accelerate and/or increase natural weight loss in postpartum. Whether the postpartum period is a teachable moment for weight loss interventions can be investigated empirically.