Delivery-related risk factors for covert postpartum urinary retention after vaginal delivery

Postpartum urinary retention (PUR) is a common consequence of bladder dysfunction after vaginal delivery. Patients with covert PUR are able to void spontaneously but have a postvoid residual bladder volume (PVRV) of ≥150 mL. Incomplete bladder emptying may predispose to bladder dysfunction at a later stage of life. The aim of this cross-sectional study was to identify independent delivery-related risk factors for covert PUR after vaginal delivery in order to identify women with an increased risk of covert PUR.

The PVRV of women who delivered vaginally was measured after the first spontaneous micturition with a portable bladder-scanning device. A PVRV of 150 mL or more was defined as covert PUR. Independent risk factors for covert PUR were identified in multivariate regression analysis.

Of 745 included women, 347 (47%) were diagnosed with covert PUR (PVRV ≥150 mL), of whom 197 (26%) had a PVRV ≥250 mL (75th percentile) and 50 (7%) a PVRV ≥500 mL (95th percentile). In multivariate regression analysis, episiotomy (OR 1.7, 95% CI 1.02 - 2.71), epidural analgesia (OR 2.08, 95% CI 1.36 - 3.19) and birth weight (OR 1.03, 95% CI 1.01 - 1.06) were independent risk factors for covert PUR. Opioid analgesia during labour (OR 3.19, 95% CI 1.46 - 6.98), epidural analgesia (OR 3.54, 95% CI 1.64 - 7.64) and episiotomy (OR 3.72, 95% CI 1.71 - 8.08) were risk factors for PVRV ≥500 mL.

Episiotomy, epidural analgesia and birth weight are risk factors for covert PUR. We suggest that the current cut-off values for covert PUR should be reevaluated when data on the clinical consequences of abnormal PVRV become available.