Association between postpartum urinary catheterization and adverse outcomes in women with obstetric anal sphincter injury: a retrospective cohort study

To evaluate whether postpartum urinary catheterization reduces urinary retention and to assess its association with adverse outcomes among women with obstetric anal sphincter injury (OASI). This retrospective cohort study included women aged 18–50 years who sustained OASI following vaginal delivery at two tertiary centers between 2015 and 2024. Patients were stratified according to postpartum urinary catheterization. The primary outcome was persistent urinary retention. Secondary outcomes included overt urinary retention, urinary tract infection (UTI), readmission, and a composite adverse outcome. Multivariable logistic regression was performed to identify independent risk factors for composite adverse outcomes. Out of 167,821 deliveries during the study period, a total of 804 women diagnosed with obstetric anal sphincter injury (OASI) were included in the analysis (0.47%). 383 (47.6%) underwent postpartum catheterization and 421 (52.4%) did not. Urinary retention was rare (0.5%), with four cases of overt retention and one case of persistent retention, precluding meaningful statistical analysis. Composite adverse outcomes, defined as presence of persistent urinary retention, urinary tract infection or hospital readmission, occurred in 43 patients (5.3%). Postpartum catheterization was independently associated with an increased risk of composite adverse outcomes (OR 3.67, 95% CI 1.81–7.43, p < 0.01). Additional independent risk factors included nulliparity (OR 3.50, 95% CI 1.22–10.05, p = 0.02) and epidural analgesia (OR 2.77, 95% CI 1.06–7.24, p = 0.03). UTI occurred in 1.6% of patients and was significantly associated with catheter use ( p < 0.01). In women with OASI, postpartum urinary retention was uncommon. Routine catheterization was not associated with reduced retention and was linked to increased morbidity, particularly UTI. These findings question the benefit of routine postpartum catheterization in this population.