1. Department of Public Health Sciences Karolinska Institutet Stockholm Sweden
2. Department of Disease Control London School of Hygiene and Tropical Medicine London UK
3. Department of Reproductive Health and Research UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction World Health Organization Geneva Switzerland
4. Ifakara Health Institute Dar‐es‐Salaam Tanzania