Randomised controlled trials (RCTs) that evaluated weight-management interventions for pregnant or postpartum women were eligible for inclusion. Eligible trials had to report a weight-related outcome measure and be of sufficient quality (details not reported).
The outcomes reported in the review were weight gain exceeding Institute of Medicine recommendations, percentage of women returning to their pre-pregnancy weight by the end of the intervention, and weight retention at one-year postpartum (after childbirth).
One included trial enrolled pregnant women of less than 20 weeks gestation, with a pre-pregnancy body mass index (BMI) of more than 19.7kg/m2. The other two trials enrolled postpartum women (three to 12 months after delivery with BMI 22kg/m2 or more at the time of recruitment for one trial, and six weeks to six months after delivery with pre-pregnancy BMI of 25 to 29.9kg/m2 for the other trial).
All included trials evaluated interventions involving both diet and exercise elements. The interventions involved individual or group educational and counselling sessions. Some trials also included newsletters, written lessons, telephone follow-up, or the keeping of food and activity diaries. The control groups of included trials received standard-of-care prenatal information on exercise and diet, or written information on healthy eating and physical activity during the postpartum period. The duration of interventions for postpartum women ranged from six to 10 months.
All potentially relevant articles were assessed independently for inclusion, with any disagreement resolved by consensus.