The vaginal epithelium in the postmenopause--cytology, histology and pH as methods of assessment

In the study of postmenopausal vaginal oestrogen deficiency, an objective assessment of the vaginal epithelium is necessary. The present study was undertaken to evaluate different methods for assessing the vaginal epithelium, during atrophic and mature conditions. The vaginal epithelium was assessed by clinical examination, pH and vaginal cytology, including morphometric analysis, before and after oestrogen treatment. Biopsies of the vaginal wall were studied using descriptive histology and immunohistochemistry methods. The antigen Ki-67, a sensitive marker of cell proliferation, was detected using the monoclonal antibody MIB1. When comparing pre- and post-treatment values from the methods, a shift towards mature values was observed, but the magnitude of the shift differed to a considerable extent. Vaginal cytology, expressed as mean maturation index (MI) shifted significantly from 94/6/0 to 0/65/35. Likewise, mean pH was significantly shifted from 6.2 to mean 4.5. The increased presence of Ki-67 positive cells could be demonstrated after oestrogen treatment, but the range of data was wide, which was also found for the thickness of the epithelium and the number of cell layers. For objective assessment of the vaginal epithelium maturation index and pH can be recommended.