The International Society for the Study of Vulvovaginal Disease Vaginal Wet Mount Microscopy Guidelines: How to Perform, Applications, and Interpretation

Objectives The aims of the study were to assess the available literature concerning the indications, performance, technique, and classification of wet mount microscopy (WMM) and to establish evidence-based recommendations. Methods Literature review from the main scientific databases was performed by the ad hoc “Vaginitis and Microbiome Committee” of the International Society for the Study of Vulvovaginal Disease. The document was approved by the executive council and membership of the International Society for the Study of Vulvovaginal Disease. Results Available data are limited and usually of low level of evidence. Nevertheless, it shows that WMM is capable of reducing misdiagnosis, overtreatment, and undertreatment of vaginal conditions. It has an excellent performance for the diagnosis of bacterial vaginosis and variable performance for trichomoniasis and candidiasis. It is the gold standard for aerobic vaginitis/desquamative inflammatory vaginitis. Currently, there is no recommendation to use WMM in the screening of asymptomatic women. The use of phase contrast is recommended to improve performance and reproducibility. Sampling location, devices, and technique have an impact on the results. Available scoring and classification scores have significant limitations. Conclusions Wet mount microscopy is a point-of-care, inexpensive, and fast technique that, with practice, can be mastered by office clinicians. It should be considered a basic skill in the curricula of gynecology and obstetrics residencies. Recommendations are provided on sampling, reading, and scoring.