Effects of Estriol-Lactobacilli Combination Versus Polycarbophil-Based Vaginal Moisturizer on Post-Radiation Vaginitis in Women With Cervical Cancer: A Randomized Controlled Trial

Objective: To compare the efficacy of an estriol-lactobacilli combination vaginal tablet (E3/L) and polycarbophil-based vaginal moisturizer (PBVM) in women with post-radiation vaginitis following cervical cancer treatment. Methods: This open-label, randomized controlled trial recruited 34 women with Stages I–III cervical cancer who had completed pelvic radiotherapy and developed vaginal toxicity symptoms. Participants were randomized 1:1 to E3/L (Gynoflor) or PBVM (Regelle) for 4 weeks. The primary outcome was change in vaginal maturation value (VMV). Secondary outcomes included changes in vaginal pH, vaginal toxicity symptom scores, and Female Sexual Function Index (FSFI) scores. Results: The median improvement in VMV was significantly greater with E3/L than with PBVM (19.65 [IQR: 0–39.5] vs. 2.08 [IQR: 0–20.1] points; p = 0.035; 95% CI: 10.22–32.59). Vaginal dryness and inflammation improved significantly in the E3/L group. Changes in vaginal pH, dyspareunia, and vaginal pain were similar between groups. Although the FSFI change was greater with E3/L (median +6 vs. +2; p = 0.01), absolute FSFI scores at Week 4 were similar, and clinical significance is uncertain. Both treatments were well tolerated. Conclusion: In women with cervical cancer and radiation-induced vaginitis, E3/L showed greater short-term improvements in vaginal epithelial maturation, dryness, and inflammation than PBVM over 4 weeks. These findings are exploratory given the modest sample size, open-label design, and short follow-up; larger double-blind randomized trials with extended follow-up are needed to confirm these results. Trial Registration: Thai Clinical Trials Registry: TCTR2024051001. © 2026 Japan Society of Obstetrics and Gynecology.