Long-term clinical and histological safety and efficacy of the CO₂ laser for treatment of genitourinary syndrome of menopause: an original study

Objective: This study aimed to evaluate histological modifications of the vaginal mucosa after repeated microablative fractional CO2 laser treatments. As secondary objectives we evaluated the clinical effects associated with repeated microablative fractional CO2 laser treatments using validated questionnaires. Methods: A prospective intervention study was performed in the Division of Gynecology and Obstetrics, Urogynecology Unit, IRCCS San Raffaele Scientific Institute with 15 postmenopausal women complaining of genitourinary syndrome of menopause symptoms. The cohort of patients was submitted to at least two previous laser treatment cycles in the past years. The Vaginal Health Index (VHI), visual analog scale (VAS), Female Sexual Function Index (FSFI), Urinary Distress Inventory-6 (UDI-6), International Consultation on Incontinence Questionnaire - Urinary Incontinence (ICIQ-UI) and 5-point Likert scale were used. Moreover, histological examinations were carried out on all samples. Results: At 4 weeks after the last treatment, the VHI score and all FSFI items were significantly increased compared with baseline. We observed a statistically significant decrease in both frequency and severity for all urinary symptoms after the follow-up. We observed a statistically significant increase in the number of epithelial cell layers with a consequent increase in epithelial thickness, in the number of glycogen-filled cells and in the number of papillae after the laser treatment. No signs of fibrosis were observed as neovascularization was observed in each woman. Conclusions: This is the first study demonstrating the histological persistency of efficacy in repeated annually laser treatment cycles, with tissue changes always leading to regenerative results without any sign of fibrosis.