Prevalence and Risk Factors of Genital Chlamydia trachomatis Infection in Sub-Saharan Africa: A Systematic Review from 1990 to 2025

Abstract Background Genital Chlamydia trachomatis ( C. trachomatis ) infection is one of the most common bacterial sexually transmitted infections (STIs) and remains a major cause of tubal infertility, ectopic pregnancy, and neonatal ocular and respiratory complications. In sub-Saharan Africa (SSA), its prevalence is likely underestimated due to limited surveillance, testing, and access to reliable diagnostic tools. This systematic review analysed data on the prevalence and risk factors of genital chlamydia between 1990 and 2025. Methods The literature search was conducted in accordance with PRISMA recommendations using PubMed/MEDLINE, Web of Science, AJOL, and Google Scholar, in English and French. Of the 754 articles identified, 47 met the inclusion criteria. Target populations included the general population, pregnant women, sex workers, people living with HIV, and infertile women. Results Reported prevalence varied widely depending on study setting and diagnostic method, ranging from 0.7% among pregnant women in Nigeria to over 60% in a hospital-based study in Cameroon. Serological tests generally overestimated prior exposure to C. trachomatis , whereas polymerase chain reaction (PCR) and nucleic acid amplification tests (NAATs) more accurately reflected active infection, with prevalences often below 10%. Identified risk factors included age under 25 years, multiple sexual partners, non-use of condoms, low socioeconomic status, and HIV co-infection. Associations between C. trachomatis infection and tubal infertility were particularly documented in Nigeria, Rwanda, and Cameroon. Conclusion This review highlights a high and likely underestimated burden of C. trachomatis infection in SSA, with significant implications for sexual and reproductive health, particularly among young people. Targeted testing of vulnerable populations, integration of screening into antenatal and HIV programs, and expanded use of molecular diagnostics are essential to improve surveillance and inform health policies. Multicentre studies in under-documented regions are needed to better estimate the true burden and guide interventions.