Vaginal micro-environment disorder promotes malignant prognosis of low-grade cervical intraepithelial neoplasia: a prospective community cohort study in Shanxi Province, China.

Purpose: Emerging evidence suggests that vaginal micro-environment disorder is closely related to the development of cervical lesions. Low-grade cervical intraepithelial neoplasia (CIN1), as an early stage of cervical lesions, exhibits a high risk of progressing to high-grade lesions or even cervical cancer. However, the effect of vaginal micro-environment on the malignant prognosis of CIN1 remains uncertain.

Methods: A total of 504 patients diagnosed with CIN1 by pathology, who were from the population-based cohorts established in Shanxi Province, China, were enrolled and followed up for 2 years. Micro-environmental factors such as vaginal pH, cleanliness, hydrogen peroxide (HO), β-glucuronidase (GUSB), leucocyte esterase (LE), and sialidase (SNA) were detected to evaluate their effect on the malignant prognosis of CIN1.

Results: Abnormal vaginal pH (HR = 1.472, 95%CI 1.071-2.022), cleanliness (HR = 1.446, 95%CI 1.067-1.960), HO (HR = 1.525, 95%CI 1.155-2.013), GUSB (HR = 1.739, 95%CI 1.235-2.448), LE (HR = 1.434, 95%CI 1.038-1.981), and SNA (HR = 1.411, 95%CI 1.065-1.870) could promote a higher incidence of CIN1 malignant prognosis, and the combined effects of these micro-environmental factors resulted in a nearly twofold increased risk (HR = 2.492, 95%CI 1.773-3.504) compared to any single factor alone, especially under the high-risk human papillomavirus (HR-HPV) infection. Notably, the cumulative incidence of malignant prognosis for CIN1 gradually increased during the early follow-up period, reaching its peak at approximately 8 months, and then stabilizing.

Conclusion: Vaginal micro-environment disorder could promote CIN1 malignant prognosis, particularly in HR-HPV-infected women. Taking micro-environmental factors as the breakthrough, our study provides a feasible vision for preventing early stage cervical lesions.