Assessing the impact, barriers and facilitators of peer-driven interventions on the prevention of mother-to-child transmission of HIV in low- and middle-income countries: A systematic review and meta-analysis

INTRODUCTION: Peer interventions may improve retention across the prevention of mother-to-child transmission (PMTCT) cascade in low- and middle-income countries (LMICs), where poor adherence to antiretroviral therapy (ART) remains a major barrier. This systematic review and meta-analysis evaluated the impact of peer support interventions on PMTCT outcomes to inform scalable strategies. METHODS: Following PRISMA guidelines, we searched PubMed, Cochrane Library, Scopus and Google Scholar (2008-2025) using terms including ‘peer mentors,’ ‘PMTCT’ and ‘LMICs.’ Independent reviewers conducted data extraction and quality appraisal using Cochrane risk-of-bias tools. Random-effects meta-analysis was performed in R (v4.4.3), with significance set at pƒ_%<ƒ_%0.05. Qualitative findings were thematically synthesized. RESULTS: Twenty-seven studies (nƒ_%=ƒ_%26ƒ_%431) across 10 countries were included. Peer interventions improved ART adherence at one year (OR: 1.19, 95% CI: 1.05-1.35) and two years (OR: 2.04, 95% CI: 1.58-2.64), PMTCT retention at six weeks postpartum (OR: 2.63, 95% CI: 1.56-4.43), infant uptake of HIV prophylaxis (OR: 2.95, 95% CI: 1.90-4.59), early infant diagnosis (OR: 1.64, 95% CI: 1.01-2.67) and viral load testing (OR: 1.21, 95% CI: 1.07-1.38). No significant effects were observed for ART initiation, PMTCT retention at 12ƒ_%months or HIV status disclosure. Most studies (75%) reported improved exclusive breastfeeding. Barriers included stigma, inadequate mentor training, logistical and economic constraints and poor male involvement; facilitators included training, incentives and community trust. CONCLUSION: Peer interventions improve adherence, infant prophylaxis and retention but have limited effects on viral suppression and disclosure. Addressing stigma, strengthening health systems and enhancing male engagement may optimize impact

• Epidemiology and Determinants of Health
  • Determinants of Health
• Determinants of Health
  • Income
  • Social support
  • Health services
  • Stigma/discrimination
  • Other
• Population(s)
  • Women
  • Children or Youth (less than 18 years old)
  • General HIV+ population
  • General HIV- population
• Prevention, Engagement and Care Cascade
  • Engagement and Care Cascade
  • Prevention
• Engagement and Care Cascade
  • Treatment
• Prevention
  • Biomedical interventions
• Testing
  • Testing
• Health Systems
  • Delivery arrangements