1. Centre for Reproductive Health, icddr,b, Bangladesh
2. Centre for Equity and Health Systems, icddr,b, Mohakhali C/A, Dhaka 1212, Bangladesh
3. Department of Epidemiology, The Centre for Public Health and Human Rights, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street/E7144, Baltimore, MD 21205, USA
4. Health Systems and Infectious Diseases Division, icddr,b, Bangladesh