Is there a correlation between the degree of proliferation of vaginal and urethral epithelium and the incidence of stress incontinence? A contribution to estrogen therapy in stress incontinence

Abstract

The extent of proliferation of the vaginal and urethral epithelium, as well as urodynamic parameters, were studied in 232 patients in order to determine whether there is a relation between the development of stress incontinence and hormone-related epithelial proliferation. A higher build-up of vaginal than of urethral epithelium was found in 74% of the patients. Even in post-menopause patients, epithelial atrophy in the vagina was only found in 29.3%, while in the urethra it was found in 61.3%. Therefore, the vaginal epithelium cannot with confidence be taken as a basis for conclusions concerning the condition of the urethral epithelium. In the group of 145 patients with urinary stress incontinence no link could be established between the extent of proliferation of the urethral epithelium, the urethral occlusion pressure and the functional length of the urethra: The occurrence of an age-related excessively low urethral occlusion pressure (hypotonic urethra) is independent of the extent of proliferation of the vaginal or urethral epithelium. Sedimentation phenomena are also seen equally frequently in cases with atrophic and eutrophic epithelium. Owing to the high percentage of overweight women among those with stress incontinence, the extent of proliferation of the vaginal and urethral epithelium often corresponds to premenopausal cell pictures even in perimenopausal and postmenopausal women; this is a consequence of increased estrogen production in the peripheral fatty tissue. Therefore, estrogen therapy is unsuccessful in women with pure urinary stress incontinence. However, the efficacy of an equivalent therapy, e.g., with estriol, has been confirmed in cases of active and combined incontinence.