1 Emergency Obstetric Care and Quality of Care Unit, WHO collaborating Centre for Research and Training in Maternal and Newborn Health, International Public Health Department, Liverpool School of Tropical Medicine, Liverpool, UK.
2 Department of Obstetrics and Gynecology, University of Nairobi, Kenya.
3 UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Sexual and Reproductive Health and Research, World Health Organization, Geneva, Switzerland.