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

INTRODUCTION AND HYPOTHESIS: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.