Should Genital Hiatus/Perineal Body Be Measured at Rest or on Valsalva?

OBJECTIVE: Genital hiatus (Gh) and perineal body (Pb) are part of the Pelvic Organ Prolapse Quantification assessment system, but it is unclear whether measurements should be taken at rest or on Valsalva. This study was designed to assess the predictive value of Gh and Pb measurements obtained at rest and on Valsalva for signs and symptoms of pelvic organ prolapse (POP). METHODS: This is a retrospective study involving 416 women who presented to a tertiary urogynecology unit with symptoms of pelvic floor dysfunction. Genital hiatus and Pb were measured at rest and on maximal Valsalva. The strength of association between binary markers of POP and measurements of Gh/Pb was estimated using logistic regression analysis. Receiver operator characteristic statistics were used to compare predictive values of Gh and Pb measurements obtained at rest and on Valsalva. RESULTS: A total of 451 women were seen during the study period. Thirty-five were excluded owing to missing data, leaving 416. Fifty-four percent (n = 223) complained of POP symptoms. On examination, 80% (n = 332) had significant POP (stage 2+ in anterior or posterior compartments or stage 1+ in the central compartment). On imaging, significant POP was diagnosed in 66% (n = 275). Mean hiatal area was 22 cm (SD, 7; range, 5-49 cm) at rest and 30 cm (SD, 10; range, 11-69 cm) on Valsalva. Genital hiatus and Pb measured on Valsalva were consistently stronger predictors of prolapse symptoms and objective prolapse (by clinician examination and by ultrasound) than at Gh and Pb measured at rest. The corresponding area under the curve values were significantly larger for Gh/Pb measures on Valsalva after adjusting for multiple confounders. CONCLUSIONS: Genital hiatus/Pb measured on maximal Valsalva is a superior predictor of symptoms and signs of POP compared with Gh/Pb at rest.