1. Department of Psychiatry, Division of Gender, Sexuality and HIV, HIV Center for Clinical and Behavioral Studies, New York State Psychiatric Institute and Columbia University Irving Medical Center, New York, NY, USA
2. Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA
3. MRU (MatCH Research Unit), Department of Obstetrics & Gynaecology, The University of the Witwatersrand, Durban, South Africa
4. Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, USA