1. Obesity Prevention Program, Department of Population Medicine, Harvard Medical School/Harvard Pilgrim Health Care Institute, Boston, Massachusetts;
2. Discipline of Obstetrics and Gynaecology, Australian Research Centre for the Health of Women and Babies, University of Adelaide, Adelaide, Australia;
3. Discipline of Paediatrics and Public Health, Australian Research Centre for the Health of Women and Babies, University of Adelaide, Adelaide, Australia;
4. Children, Youth, and Women's Health Service, Public Health Research Unit, Adelaide, Australia.