Inclusion Criteria:  Sex female Age 18-45 years Desire to use LNG implant (for at least 6 months) or for at least one cycle of use of DMPA injectable (3 months), following comprehensive client-centered contraceptive counselling Willing and able to initiate the LNG implant or the DMPA injectable at enrolment visit or soon thereafter Participants who are engaging in sexual activity that could lead to pregnancy must agree to use a non-hormonal method of contraception, in addition to the LNG implant or DMPA injectable, while participating in the study. Acceptable contraceptives include: condoms (male or female); diaphragm or cervical cap with spermicide; non-hormonal intrauterine device; bilateral tubal ligation; and male partner vasectomy No acute infections or other opportunistic diseases requiring systemic medication of hospitalisation within 14 days prior to study entry  The following laboratory values:  Haemoglobin ≥8.0 g/dL Creatinine clearance >60 mL/min/1.73m2 Aspartate transaminase (AST; serum glutamic oxaloacetic transaminase (SGOT)) <2.5 x upper limit of normal ULN Alanine transaminase (ALT; serum glutamic pyruvic transaminase (SGPT)) <2.5 x ULN Platelet count ≥50,000 platelets/mm3 Last menstrual period ≤35 days prior to study entry No sexual activity that could lead to pregnancy since last menstrual period without contraception (condoms, male or female); diaphragm or cervical cap with spermicide; non-hormonal intrauterine device; bilateral tubal ligation; and male partner vasectomy), as reported by study participant and assessed by study clinician Negative serum or urine pregnancy test at screening and study enrolment Willing to undergo questionnaires, examinations and phlebotomy per schedule for the duration of the study period Able to consent for study participation in English or Setswana  For HIV-positive participants:  Documented HIV-1 infection Using DTG-based ART (DTG 50mg once daily co-administered with 2 NRTIs (emtricitabine/tenofovir or lamivudine/tenofovir) DTG-based ART use (for at least 30 days prior to contraceptive method initiation). On stable regimen containing DTG and 2 NRTIs for ≥ 30 days without gaps in adherence in the last 30 days prior to study entry, and no known plans to change ART regimen for the duration of the study Most recent HIV plasma RNA below lower limit of quantitation of the assay used per standard of care  Exclusion Criteria:  Sex male Women <18 years Any contraindication (WHO Medical Eligibility Criteria for Contraceptive Use Category 3 or 4) to receiving the selected contraceptive method, based on WHO Medical Eligibility Criteria for Contraceptive Use (24) Postpartum less than 6 weeks Currently breastfeeding Currently pregnant or intends to become pregnant during the study  The following laboratory values:  Hemoglobin <8.0 g/dL Creatinine clearance ≤60 mL/min/1.73m2 Aspartate transaminase (AST; SGOT) ≥2.5 x ULN Alanine transaminase (ALT; SGPT) ≥2.5 x ULN Platelet count <50,000 platelets/mm3 Receipt of DMPA during the 120 days or norethisterone enanthate (NET-EN) during the 60 days prior to study entry Initiated the LNG implant prior to study entry Receipt of other hormonal treatments (e.g., oral contraceptives, contraceptive vaginal ring, contraceptive patch, or oral hormone replacement therapy) within the 30 days prior to study entry The study puts the participant at unacceptable risk based on the judgment of the study staff Known allergy/sensitivity or any hypersensitivity to components of study medication(s) or their formulation Active drug or alcohol use or dependence that would interfere with adherence to study requirements Concomitant use of drugs known to be contraindicated with LNG or MPA Use of any drugs known to: 1) induce CYP3A4 system within 30 days or 2) inhibit the CYP3A4 system with one week prior to enrolment visit Use or anticipated use of concomitant enzyme-inducing drugs, including but not limited to rifampicin for tuberculosis treatment and anti-convulsant medications (e.g., phenytoin, carbamazepine, barbiturates, primidone, topiramate, oxcarbazepine, felbamate) Unwilling to attend study visits or adhere to study visit procedures Unable to consent  For HIV-positive participants:  Self-reported non-adherence to ART Concomitant use of drugs known to be contraindicated with DTG or medicinal products that reduce DTG exposure (e.g. magnesium/ aluminium-containing antacid, iron and calcium supplements, multivitamins and inducing agents, rifampicin, St. John's wort and anti-epileptic medicinal products carbamazepine, oxcarbazepine, phenytoin and phenobarbital)