Table 2 Characteristics of included studies

Jefferies, K., Shub, A., Walker, SP., Hiscock, R & Permezel, M.

2009,

Reducing excessive weight gain in pregnancy: a randomised controlled trial.

RCT,

Melbourne, Australia.

To assess the effect of regular weight measurements and advice about the recommended (IOM 1990) weight ranges on gestational weight gain (GWG).

Neutral (−)

Pregnant women recruited before ≤14 week’s gestation.

Age >18 years.,<45 years., singleton pregnancy. English speaking, no pre-existing Type1 or 2 diabetes Intervention (I₁) n = 148 (−23), Control (C) n = 138 (−27)

(I₁) Weight measurements + advice compared to standard antenatal care (C).

BMI calculated at first antenatal visit and advice on optimal weight gain given as per IOM 1990 guidelines.

I₁ self-weighing recorded on participants own antenatal card at first visit, 16, 20, 24, 28, 30, 32, 34 and 36 weeks.

(C) Weighed at first visit and at 36 weeks only.

(I₁) Weight self-recorded on personalised measurement card (tabular or graphical), using scales at hospital or participant’s home until 34 weeks

(I₁) + (C) weighed at recruitment & 36 weeks on hospital scales.

Mean difference in weight gain (Kgs/week) and between BMI subgroups.

Total weight gain and proportion gaining in excess of the IOM 1990 weight gain guidelines.

Maternal & neonatal pregnancy and birth complications

No difference in total weight gain Kgs/week) between (I₁₎ and (C).

A statistically significant reduction in GWG (Kgs/Week.) between (I₁) and (C) in overweight BMI subgroup only (mean difference of 0.12 kg/week (95% CI, 0.03 to 0.22),

p = 0.01.

Weight measurements were largely self-reported based on home and hospital scales. There was no measure of participation compliance with the (I₁). A small sample size was used with inadequate power to detect differences between groups for weight gain above IOM 1990 guidelines, pregnancy and neonatal complications.

Brownfoot, FC. Davey, MA. & Kornman, L.

2016

Routine weighing to reduce excessive antenatal weight gain: A randomised controlled trial.

RCT

Melbourne, Australia.

To assess the effect of clinician weighing at each antenatal visit with advice on appropriate GWG using the IOM 2009 weight gain in pregnancy guidelines.

Positive (+)

Pregnant women recruited <21 weeks gestation.

Age >18 years <45ys, singleton pregnancy. English speaking, no co morbidities or substance abuse identified.

Intervention (I₁) n = 386 (−17),

Control (C) n = 396 (−24)

(I₁) Weight recorded by a clinician at each antenatal appointment and documented in hospital antenatal record. The treating clinician encouraged to discuss weight gain (no scripted responses used). (C) Routine antenatal care including advice of appropriate weight gain within the IOM 2009 ranges. Both groups weighed at recruitment with BMI calculated. The (C) weighed again at ≥36 weeks gestation.

(I₁) Weight documented in hospital antenatal records at appointments by attending clinicians.

(C) Weighed at recruitment and ≥ 36 weeks only and documented on hospital antenatal record. Data collected from the antenatal hospital record, mean frequency of weight measurements reported for both groups.

Mean difference in weight gain per week (Kgs/week) and between BMI subgroups. Proportion gaining within, less than and more than the IOM 2009 weigh gain ranges. Maternal & neonatal pregnancy and birth complications

No statistically significant differences reported in mean weight gain per week (I₁) 0.54 kg (±0.28) & (C) 0.53 kg (±0.24) p = 0.63 (p = 0.05).

No difference in proportion of women gaining weight within, less than or more than IOM 2009 guidelines. No differences between groups for all neonatal and maternal complications.

Study not powered to detect a between group differences for all maternal and neonatal pregnancy and birth complications reported.