1. Department of Reproductive Health and Research, World Health Organization, avenue Appia 20, Geneva 27, Switzerland.
2. Perinatal Institute, Birmingham, England.
3. Department of Obstetrics and Gynaecology, University of Pretoria, Pretoria, South Africa.
4. Department of Obstetrics, University Medical Center Groningen, Groningen, Netherlands.
5. Mater Research Institute, University of Queensland, Brisbane, Australia.
6. Department of International Public Health, Norwegian Institute of Public Health, Oslo, Norway.
7. Centre for Women’s Health Research, University of Liverpool, Liverpool, England.
8. Department of Maternal, Newborn, Child and Adolescent Health, World Health Organization, Geneva, Switzerland.