PurposeWe aim to identify patients at risk for post-operative urinary retention (POUR) and factors associated with POUR.MethodsMales who underwent inguinal hernia repair (IHR) from June 2010 to September 2014 at a single institution were grouped according to the presence (symptomatic) or absence (asymptomatic) of preoperative urogenital symptoms (UGS). Patients ≤ 18 years of age were excluded. POUR was defined as the need to catheterize a patient who had not voided 6 h after surgery. Data were examined using IBM SPSS v23.0.ResultsOf the 60 asymptomatic and 30 symptomatic patients identified, no differences were seen in age (55 vs. 65, p = 0.13), length of stay > 1 day (3% vs. 13%, p = 0.09), bilateral inguinal herniation (23% vs. 23%, p = 1.00), or laparoscopic approach (70% vs. 69%, p = 1.00); however, significant differences were seen in POUR (5% vs. 27%, p = 0.01) and α-blocker utilization (50% vs. 80%, p = 0.01). When age-matched, neither POUR (10% vs. 27%, p = 0.10) or α-blocker utilization (57% vs. 80%, p = 0.05) significantly differed between asymptomatic and symptomatic patients, respectively. Logistic regression analysis demonstrated that only bilateral inguinal herniation (OR 6.55, p = 0.03) and symptoms (OR 6.78, p = 0.02) were associated with POUR. Asymptomatic patients with a unilateral hernia have a 4.3% risk of POUR, whereas symptomatic patients with a bilateral inguinal hernia have at 57.1% risk.ConclusionsWe demonstrate that bilateral inguinal herniation and UGS independently increase the risk of POUR, whereas α-blockers do not. For the general surgical population, α-blockers should not be routinely prescribed to all patients and instead should be limited to high-risk patients.