The Institute of Medicine (IOM) GWG guidelines [4] provided the GWG recommendations. The nutrition content is based on the recommendations of the Australian Dietary Guidelines
for pregnancy [41] with emphasis on replacement of sugar-sweetened beverages, increased fruit and vegetable intake, reduction of discretionary food groups and consumption of regular meals. The physical activity components are also based on national guidelines for pregnancy
[42,43]. The emphasis is on 30 minutes of moderate intensity physical activity on most, if not all, days of the week, reduction of sedentary behaviour and abdominal and
pelvic floor strengthening. The behaviour change guidance is informed by the CALO-RE taxonomy of behaviour change techniques [44]. An additional file shows the mapping of intervention content to theoretical constructs (see Additional file 2).