The primarily objective of this study is to assess the effect of switching from Tenofovir Disoproxil Fumurate (TDF) to TAF based ART on bone mass and turnover among women on DMPA for contraception. HIV virologically suppressed women on DMPA will be switched from their TDF based regimen to Bictergravir /Emtricitabine / Tenofovir alafenamide (B/F/TAF; Biktarvy®) in a randomized fashion. HIV infected women on TDF and non-hormonal contraception will be switched to Biktarvy®).

Inclusion Criteria:

• Age 20 through 40 years (inclusive) at screening, verified per site SOPs
• Able and willing to provide written informed consent to be screened for and to take part in the study.
• Able and willing to provide adequate locator information, as defined in site SOPs
• Previously participated in the BONE: CARE study. Additional women will be recruited from the health centers where the BONE: CARE participants were receiving HIV care, and these will be matched to those from the BONE: CARE cohort based on age, duration on ART and contraception use.
• Per participant report, plans to stay in the study catchment area in the next 24 months
• Per participant report, willing to continue using similar contraceptive method as in the BONE: CARE study.

Exclusion Criteria:

• Currently pregnant/ breastfeeding or was pregnant/ breastfeeding in the last 6 months prior to screening
• Intentions to get pregnant in the next two years
• History of active tuberculosis
• Pathologic bone fracture not related to trauma (ever)
• Has pre-existing condition known to affect bone metabolism (e.g. thyrotoxicosis, tuberculosis, diabetes mellitus, liver or renal disease)
• Is taking the following medications known to interfere with bone metabolism (steroids, anti-convulsants, bisphosphonates, cancer drugs, etc.).

20 - 40 year old HIV-infected non pregnant women