Total vaginal length : does it matter for assessing uterine prolapse?

Introduction and hypothesis: Using the International Continence Society Pelvic Organ Prolapse Quantification (ICS POP-Q) system, uterine prolapse staging requires measurement of total vaginal length (TVL). The aim of this study was to determine whether TVT is a confounder of the relationship between uterine descent and POP symptoms. Methods: This is a retrospective study on 721 patients seen in a tertiary urogynaecological unit. All patients had undergone a standardised, in-house, physician-led questionnaire and digital POP-Q examination. Patients with a history of hysterectomy or with a dominant prolapse in the anterior ± posterior compartment were excluded from analysis, leaving 393 complete data sets for analysis. Association between prolapse symptoms (lump/drag) and station of cervix (i.e. C) were tested. Age, body mass index (BMI), menospausal status and vaginal parity were tested as potential confounders. Variables that were significant on binary logistic regression (P < 0.05) were included in a model for receiver operting characteristic (ROC) statistical analysis. This was repeated after adding TVL to the model. Likelihood ratio test was performed to compare models. Results: On binary logistic regression, prolapse symptoms were significantly associated with C, menopausal status and TVL (all P < 0.03). ROC analysis yielded an area under the curve (AUC) of 0.75 with menopausal status and C in the model. Adding TVL yielded an AUC of 0.773. The difference is statistically significant on the likelihood ratio test (P < 0.001). Conclusions: Adding TVL improved the performance of cervical station in predicting prolapse symptoms, validating the practice of using TVL in staging uterine prolapse.