Harnessing the Vaginal Microbiome: A New Frontier in the Prevention of Sexually Transmitted Infections Publisher Pubmed



Mohammadzadeh R ; Rajabi E ; Saadoon Abbood R ; Hasan R N ; Navidifar T ; Bostanghadiri N
Source: Expert Reviews in Molecular Medicine Published:2026

Abstract

Background The vaginal microbiome plays a vital role in maintaining reproductive and urogenital health in females. In healthy women, it is dominated by Lactobacillus species, including L. crispatus, L. gasseri, L. iners, and L. jensenii. These species provide strong protection against sexually transmitted infections (STIs) and other gynecological diseases. They produce lactic acid, which helps maintain a low vaginal pH, supporting epithelial integrity, modulating the immune system, and preventing colonization by bacterial pathogens. Dysbiosis, or an imbalance in microbial communities, is linked to higher susceptibility to infections like Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, HIV, and HPV. The vaginal microbiota is dynamic and can change in response to hormonal shifts, sexual activity, antibiotic use, hygiene practices, and the duration of infection. Methods This review provides a thorough overview of the composition, functions, and protective mechanisms of a healthy vaginal microbiome. Results: Recent research has shown that microbiome-based therapies, such as probiotics, prebiotics, synbiotics, and vaginal microbiota transplantation, may help restore vaginal microbial balance. Additionally, introducing engineered strains like L. jensenii that produce anti-HIV proteins offers promising new approaches to HIV treatment. Conclusions This review also emphasizes therapeutic strategies aimed at stabilizing the vaginal microbiota to lower STI risk. © The Author(s), 2026. Published by Cambridge University Press.