Ferrara 2011.

Methods	Computer‐based randomisation.
Participants	197 English‐speaking women with gestational diabetes mellitus, aged 18 years or older without high‐risk pregnancy (i.e., drug or alcohol abuse, chronic health problems, or pregnancy complications).
Interventions	Intervention: Intervention was initiated during pregnancy and continued until 12 months postpartum. Intervention consisted of advice on diet, exercise and breastfeeding. 2 trained dietitians delivered the intervention. The prenatal phase consisted of 1 in‐person session and 2 individual telephone counselling contacts. During the postpartum phase women were asked to reach their weight goal during the first 12‐months postpartum and were given a handbook that contained written materials organized in 16 sessions. There was a core curriculum of 8 sessions with up to 8 additional sessions offered to those who desired more contact. The sessions were conducted over the telephone except for the first and the last, which were conducted in‐person. Women were encouraged to perform 150 min of moderate or harder physical activity per week and to consume 25% or less of total calories from fat per day. Control: women received usual care and printed educational materials that included publicly available information on gestational diabetes mellitus. In the postpartum period, they received 2 newsletters focusing on issues related to infant safety and general health. Trial duration: long‐term.
Outcomes	Percentage of women who returned to prepregnancy weight if it was normal, or achieved a 5% reduction from prepregnancy weight if overweight at 6 weeks, 7 and 12 months postpartum, percentage of partial or exclusive breastfeeding at 6 weeks and 7 months postpartum, satisfaction and compliance with intervention Data on weight at 12 months postpartum were preferably used in the analysis. Other outcomes not considered in this review: change in percent of calories from dietary fat and change in moderate or vigorous physical activity (min/ wk) at 6 weeks and 7 months postpartum.
Notes	Small differences in baseline characteristics were observed between women in the intervention and usual care conditions regarding education and 1‐h glucose value from the diagnostic 100 g oral glucose tolerance test (lower values in the intervention group). In total, 197 women enrolled in the study. Participant retention at 12 months postpartum was 75% in the intervention group and 83% in the control group.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation	Low risk	Randomisation was computer‐based.
Allocation concealment	Unclear risk	No details provided.
Blinding All outcomes	Low risk	Data were collected by research assistants who were unaware of the condition assignment.
Incomplete outcome data addressed All outcomes	High risk	21% of loss to follow‐up.
Free of selective reporting	Low risk	Outcomes of relevance described.
Free of other bias	Unclear risk	Supported by a grant (R18‐DK067334) from the National Institute of Diabetes and Digestive and Kidney Diseases and a grant from the Kaiser Garfield Foundation. No mention of any research protocol published a priori. The characteristics of participants were slightly different between groups at baseline.