1. LSE Health, London School of Economics and Political Science, Houghton Street, London WC2A 2AE, UK
2. Centre for Reproductive Health Research and Innovation, Lagos State University College of Medicine, Oba Akinjobi Street, Ikeja, P.M.B. 21266, Lagos, Nigeria
3. Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
4. School of Geographical Sciences and Urban Planning, Arizona State University, South Myrtle Avenue, Tempe, Arizona 85281, USA
5. Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
6. Department of Community Health and Primary Care, College of Medicine, University of Lagos, Idi Araba, PMB 12003, Lagos, Nigeria
7. Department of Community Health and Primary Health Care, Lagos State University College of Medicine, Oba Akinjobi Street, Ikeja, P.M.B. 21266, Lagos, Nigeria
8. Department of Epidemiology and Medical Statistics, University of Ibadan, Oduduwa Road, 200132, Ibadan, Nigeria
9. Office of the Commissioner, Lagos State Ministry of Health, Secretariat, Alausa, Lagos, Nigeria
10. Department of Obstetrics and Gynaecology, College of Medicine of the University of Lagos, Idi Araba, P.M.B 12003, Lagos, Nigeria
11. Department of Public Health, Institute of Tropical Medicine, Kronenburgstraat 43, 2000 Antwerpen, Belgium