1 UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland.
2 UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland.
3 Communicable Diseases and Environmental Determinants of Health Department, Pan American Health Organization (PAHO), Washington, DC, USA.
4 Center for Perinatology, Women's Health, and Reproduction (CLAP/PAHO), Montevideo, Uruguay.