Funding for this research was provided by:
National Institutes of Health (AI51794, D43TW00231)
National Research Foundation (67385)
National Research Foundation (96354)
South African Medical Research Council (MRC-RFA-UFSP-01-2013/UKZN-HIVEPI)
Contraception Research and Development (GP00-08-00005-00, PPA-09-046)
Received: 9 July 2017
Accepted: 15 January 2018
First Online: 25 January 2018
Ethics approval and consent to participate
: Ethical approval for the study was obtained from the Research Ethics Committees of the University of KwaZulu-Natal (E013/04) and University of Cape Town (025/2004). All participants provided written, informed consent to participate in the study.
: Consent to publish was obtained from EC1 and EC2.
: None of the authors have any competing interests to declare.
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