Risk factors for acute postpartum urinary retention after vaginal delivery: focus on episiotomy direction

Objective: This study aimed to investigate the independent factors for acute postpartum urinary retention (APUR) after vaginal delivery.Methods: From January 2008 to December 2013, 98 patients with APUR after vaginal delivery without instrument use were compared with 108 control patients matched by age and medical history. Multivariate logistic regression analysis was performed to identify independent risk factors for APUR. Predictive accuracy for the multivariate model was assessed using the derived area under a receiver operating characteristics curve.Results: Among maternal previous partial history, mean live birth history was lower in the APUR group (0.12 versus 0.31, p=0.017). Regional anesthesia use (76.5% versus 60.2%, p=0.036), mediolateral episiotomy (63.3% versus 31.5%, p<0.001) and labor time were significantly higher in the APUR group. Multivariate logistic regression analysis showed that mediolateral episiotomy, labor time and the presence of regional anesthesia were independent contributing factors for the development of APUR. This model's predictive accuracy for APUR was 73.1%.Conclusion: Prolonged labor time, regional anesthesia and mediolateral episiotomy were independent factors for APUR. Therefore, we considered median episiotomy to be the best approach during vaginal delivery avoiding APUR.