Kuwa Free! - Live Free!

Inclusion Criteria (PK study): * Female sex, * HIV-positive (for PK groups #1-4) or HIV-uninfected (for PK group #5 only), * Age 15-24 years at the time of enrollment, * Documented or confirmed viral suppression for HIV (defined as \<40 copies/mL) within 6 months prior to study enrollment, * Have been on the study oral drug for at least 4 weeks for the PK groups #1-4, * Have initiated and intends to use DMPA or implant for at least another three or 6 months, respectively, * Willing to undergo phlebotomy every 4-12 weeks for the duration of the study period * Able to consent or assent (with parental consent) for study participation in English or Kiswahili Exclusion Criteria (PK study): * Already be on ART that concurrently contains combinations of non-nucleoside reverse transcriptase inhibitors (NNRTIs), such as efavirenz, and protease-inhibitors (PIs), such as atazanavir/ritonavir or lopinavir/ritonavir, or integrase inhibitors (INSTIs), such as raltegravir or dolutegravir * Currently pregnant or intends to become pregnant or breastfeeding within the next 12 or 24 weeks for DMPA or implant groups, respectively, * Have had unprotected sex in the last two weeks or be currently pregnant via urine pregnancy testing, * Use or anticipated use of drugs for the duration of the study period known to interact with hormonal implants or the study ART regimen, * Current or planned concomitant use of other hormonal contraceptives, * Be obese (BMI≥30), * Evidence of Hepatitis B virus (HB…