Methods	Randomised controlled trial, set in an obstetric clinic for low-income women at a hospital in Pittsburgh, PA, USA
Participants	Inclusion criteria: pregnant women before 20 weeks of gestation. (Subjects were recruited in to 4 cells; normal and overweight, black and white.) Exclusion criteria: underweight women, younger than 18 years, 1st prenatal visit > 12 weeks’ gestation, high-risk pregnancy (i.e.. drug abuse, chronic health problems, previous complications during pregnancy, current multiple gestation)
Interventions	Intervention (n = 57): the intervention was provided at regular scheduled clinic visits by staff with training in nutrition or clinical psychology. Education about weight gain, healthy eating, and exercise and individual graphs of their weight gain Shortly after recruitment, written and oral information were given in the following area: appropriate weight gain, exercise, healthy eating.Newsletters prompting healthy eating and exercise habits were mailed bi-weekly. After each clinic visit, women were sent a personalised graph of their weight gain Those exceeding weight gain goals were given additional individualised nutrition and behavioural counselling using the format listed; a stepped care approach Control (n = 53): usual care: standard nutrition counselling provided by the physicians, nurses, nutritionists and WIC counsellors. This counselling emphasised a well-balanced dietary intake and advice to take a multivitamin/iron supplement
Outcomes	Excessive weight gain, total weight gain, low weight gain. Low birthweight infants, macrosomia infants, preterm delivery, caesarean delivery, pre-eclampsia, weight retention at 4 weeks’ postpartum Total weight gain was based on self-reported prepregnancy weight and weight at last clinic visit prior to delivery
Notes	Excessive weight gain categorised as above the IOM recommendations Low weight gain categorised as below the IOM recommendations IOM recommends a weight gain of 6.8-11.3 kg for overweight women (BMI of 26-29) and a weight gain of 6.8 kg (with no specified upper limit) for obese women (BMI > 29) Age of participants 25.5 ± 4.8. Gestational age at recruitment (intervention, control): 14.7 ± 3.1 weeks BMI category, n (intervention, control): normal weight (BMI19.8-26): 30, 31; overweight (BMI > 26): 27, 22.
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Women were randomly assigned to the standard care control group or to the intervention
Allocation concealment (selection bias)	Unclear risk	No information provided.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	No information provided.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Using intention-to-treat approach. Loss to follow-up < 10%.
Selective reporting (reporting bias)	Unclear risk	Could not determine.
Other bias	High risk	Refusal rates were higher among black women (28/74 refused) than among white (16/90 refused), and higher in overweight black women than in any of the other 3 weight-by-race categories