Role of Vaginal Microbiota Dysbiosis in Gynecological Diseases and the Potential Interventions Original paper

What was reviewed?

This review comprehensively examines the role of vaginal microbiota dysbiosis, primarily the loss of Lactobacillus dominance and increased microbial diversity, in the pathogenesis and progression of a wide range of gynecological diseases, both infectious (e.g., bacterial vaginosis [BV], vulvovaginal candidiasis, trichomonal vaginitis, atrophic vaginitis, sexually transmitted infections including HPV, HSV-2, HIV, Neisseria gonorrhoeae, Mycoplasma genitalium, and Chlamydia trachomatis) and non-infectious (e.g., miscarriage, preterm birth, infertility, polycystic ovarian syndrome [PCOS], uterine fibroids, menstrual disorders, and intrauterine adhesions). The review also evaluates current and emerging interventions, including antibiotics, probiotics, and the novel approach of vaginal microbiota transplantation (VMT), to restore healthy microbial balance and mitigate disease risk and recurrence.

Who was reviewed?

The review encompasses studies involving a diverse population of women across different reproductive stages and clinical conditions, including those with various gynecological infections, infertility, endocrine disorders, and other non-infectious diseases. It references observational, clinical, and interventional research, from healthy women (to characterize community state types of the vaginal microbiome) to patients suffering from BV, recurrent infections, PCOS, and other gynecological pathologies. The included studies span multiple age groups, menopausal statuses, and geographic regions, offering a broad perspective on vaginal microbiota’s clinical significance.

Most important findings

A healthy vaginal microbiota is typically dominated by Lactobacillus species, primarily L. crispatus, L. gasseri, L. jensenii, and L. iners, which maintain vaginal acidity, produce antimicrobials, and modulate immune responses, thereby protecting against pathogens. Dysbiosis is characterized by a reduction in Lactobacillus and an increase in diverse anaerobes such as Gardnerella, Atopobium, Prevotella, Megasphaera, Leptotrichia, Sneathia, and fungi like Candida. This shift is strongly associated with increased susceptibility to infections (BV, VVC, trichomoniasis, STIs), adverse reproductive outcomes (miscarriage, preterm birth, infertility), and endocrine/metabolic disorders (PCOS, uterine fibroids, menstrual disorders). The review highlights that antibiotic use, while effective, is limited by recurrence and resistance; probiotics show promise, particularly strains restoring Lactobacillus dominance, but clinical outcomes are variable. Notably, the review details the first clinical application of VMT, with promising results in refractory BV, suggesting its potential as a robust restorative therapy. Altered vaginal microbial signatures, such as decreased Lactobacillus and increased Gardnerella/Prevotella in BV, or increased Mycoplasma/Prevotella and decreased L. crispatus in PCOS, could serve as important biomarkers for clinical risk stratification and therapeutic targeting.

Key implications

The clinical management of gynecological diseases can be significantly improved by integrating strategies to modulate the vaginal microbiota. While antibiotics remain the standard of care, their limitations necessitate adjunctive or alternative therapies. Probiotics, particularly those containing key Lactobacillus species, can reduce recurrence and improve outcomes in both infectious and non-infectious gynecological conditions. VMT emerges as a highly promising intervention, capable of re-establishing a resilient, healthy vaginal microbiota, particularly for recurrent or treatment-resistant BV. However, broader clinical adoption requires larger trials, standardized protocols, and robust safety assessments. For clinicians, understanding the microbial signatures associated with specific diseases allows for more personalized, microbiome-informed therapeutic approaches and risk prediction.