Background: Recurrent vaginal infections remain a major clinical challenge, particularly in women experiencing persistent or relapsing symptoms despite conventional antimicrobial therapy. Increasing evidence suggests that recurrence may be associated not only with the presence of specific pathogens but also with disruption of the vaginal microbial ecosystem. Lactobacillus crispatus is strongly associated with vaginal stability and low pH, whereas Lactobacillus iners may predominate in transitional or dysbiotic microbial states.

Objective: To characterize vaginal microbiota profiles in women with recurrent vaginal infections and explore the relationship between L. crispatus, L. iners, vaginal pH, and the presence of potentially pathogenic microorganisms.

Methods: A cross-sectional descriptive study was conducted in 39 women aged 28–55 years with recurrent vaginal infections, defined as ≥3 episodes per year. Vaginal samples collected between November 2024 and July 2025 were analyzed using a microfluidic real-time PCR panel targeting 39 microorganisms. Vaginal pH was assessed, and an exploratory L. iners/L. crispatus index was calculated to characterize Lactobacillus-dominance patterns.

Results: L. crispatus predominance was identified in 35.9% of participants, while L. iners predominance was observed in 30.8%. An L. iners/L. crispatus index >1 was present in 41% of the cohort and in 55% of Candida-associated profiles. Reduced L. crispatus abundance was frequently observed in samples containing Streptococcus spp., Gardnerella vaginalis, and Candida spp. Transitional/L. iners-dominant profiles showed greater microbial co-detection and were associated with elevated vaginal pH, with a median pH of approximately 6.0. Frequent co-detection of Candida spp., G. vaginalis, and Atopobium vaginae highlighted the polymicrobial nature of recurrent vaginal dysbiosis.

Conclusion: Women with recurrent vaginal infections exhibited heterogeneous but frequently disrupted vaginal microbial profiles characterized by reduced L. crispatus, increased representation of L. iners, elevated vaginal pH, and polymicrobial co-detection. These findings support a shift from pathogen-centered assessment toward an ecological evaluation of the vaginal microbiota. Prospective longitudinal studies are required to determine whether restoration of L. crispatus-dominant communities can improve microbial stability and reduce recurrence.

Cristian Hidalgo Pajuelo is a Peruvian gynecologist and obstetrician and founder of ILAGINE – Instituto Latinoamericano de Ginecología. His clinical and research work focuses on the vaginal, endometrial, and intestinal microbiota and their relationship with recurrent gynecological and urinary infections. His research interests include recurrent vulvovaginal candidiasis, vaginal dysbiosis, Lactobacillus crispatus, vaginal pH, recurrent urinary tract infections, and microbiome-based precision medicine. He has participated in clinical research and scientific publications exploring microbiota-centered approaches to recurrent infections and is actively developing translational research integrating microbial profiling with clinical gynecology.