Vaginal microecological diversity and Ureaplasma urealyticum co-infection in high-risk HPV infection: a cross-sectional study.

BACKGROUND

Persistent high-risk human papillomavirus (HR-HPV) infection is a key driver of cervical carcinogenesis. Vaginal microecology acts as a host defense barrier, and its dysbiosis may affect HPV clearance. The interplay among microbial diversity, viral load, and sexually transmitted pathogens remains unclear.

METHODS

This cross-sectional study enrolled 330 women from a gynecological clinic in Shanghai (December 2025 - February 2026). HR-HPV genotyping and viral load were determined by fluorescence quantitative PCR. Vaginal culturable bacteria were identified using MALDI-TOF MS, and culturable bacterial richness (Sobs index) were calculated. Routine vaginal parameters and sexually transmitted pathogens (Chlamydia trachomatis, Neisseria gonorrhoeae, Ureaplasma urealyticum [UU]) were assessed. Microecological characteristics were compared between HR-HPV-positive and -negative groups, with subgroup analyses within the positive group by viral load, genotype, and single/multiple infection.

RESULTS

The HR-HPV positivity rate was 43.94% (145/330), with HPV52, HPV53, and HPV16 being predominant, and the highest rate in women >50 years. The HR-HPV-positive group had significantly higher bacterial richness (Sobs index) than the negative group (all P<0.05). Among positive patients, those with high viral load (logarithm >4) had significantly higher Sobs index than those with low viral load (P < 0.05). Proportions of patients with pH>4.5, positive H2O2, positive leukocyte esterase, and Lactobacillus count <20 were significantly higher in the positive group (all P<0.05). UU positivity was significantly higher in the positive group (78.1% vs. 52.3%, P<0.05), while CT and NG showed no significant differences. Within the positive group, no significant differences in diversity or routine parameters were observed across subgroups (all P>0.05).

CONCLUSION

HR-HPV infection is associated with elevated culturable bacterial richness and dysbiosis; high viral load correlates with more pronounced microbial alterations. UU co-infection is positively associated with HR-HPV. These findings support incorporating vaginal microecological assessment and UU screening into HR-HPV management strategies.