BACKGROUND: Comprehensive analyses are lacking to identify predictors of postoperative complications in patients who undergo a Hartmann reversal. OBJECTIVE: The aim of this study is to identify predictive factors for morbidity after reversal. DESIGN: This study is a retrospective review of prospectively collected data. SETTINGS: The study was conducted at Cleveland Clinic Florida. PATIENTS: Consecutive patients from January 2004 to July 2011 who underwent reversal were included. MAIN OUTCOME MEASURES: Variables pertaining to Hartmann procedure and reversal were obtained for analyses in patients with and without postoperative complications. Univariate and multivariate analyses were performed. RESULTS: A total of 95 patients (mean age 61 years, 56% male) underwent reversal, with an overall morbidity of 46%. Patients with and without complications had similar demographics, comorbidities, diagnoses, and Hartmann procedure intraoperative findings. Patients with complications after reversal were more likely to have prophylactic ureteral stents (61% vs 41%, p < 0.05) and an open approach (91% vs 75%, p < 0.04). Complications were associated with longer hospital stay (8.8 vs 6.9 days, p < 0.006) and higher rates of reintervention (9% vs 0%, p < 0.03) and readmission (16% vs 2%, p < 0.02). Predictors of morbidity after reversal included BMI (29 vs 26 kg/m(2), p < 0.04), hospital stay for Hartmann procedure (15 vs 10 days, p < 0.03), and short distal stump (50% vs 31%, p < 0.05). BMI was the only independent predictor of morbidity (p < 0.04). Obesity was associated with significantly greater overall morbidity (64% vs 40%, p < 0.04), wound infections (56% vs 31%, p < 0.04), diverting ileostomy at reversal (24% vs 13%, p < 0.05), and time between procedures (399 vs 269 days, p < 0.02). LIMITATIONS: This study was limited by its retrospective design. CONCLUSIONS: Hartmann reversal is associated with significant morbidity; BMI independently predicts complications. Therefore, patients who are obese should be encouraged or even potentially required to lose weight before reversal.