Thirty-Day Incidence and Risk Factors for Lower Urinary Tract Fistula After Hysterectomy

Lower urinary tract (LUT) fistulas are rare but morbid complications after hysterectomy. Contemporary population-level data on incidence and risk factors are limited.

The objective of this study was to determine the incidence and risk factors for lower urinary tract fistulas within 30 days after hysterectomy using a national surgical database.

This was a retrospective cohort study using hysterectomy-targeted files from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) from 2014 to 2020. Women undergoing hysterectomy who developed a LUT fistula were identified. The incidence of LUT fistula was determined. Univariate analysis assessed putative risk factors, and stepwise logistic regression identified independent predictors.

Between 2014 and 2020, 226,398 hysterectomy cases were identified. The incidence of LUT fistula was 0.1% (n=222), including 106 ureterovaginal, 107 vesicovaginal, and 9 combined LUT fistulas. The mean age of patients who developed a LUT fistula was 48.6±10.6 years compared with 50.7±13.0 years for those who did not (P=0.005). Among patients who underwent hysterectomy for malignancy, the LUT fistula incidence was 0.14% (n=74). Wound classification and gynecologic malignancy were significant risk factors (P<0.001). Postoperative ureteral obstruction was strongly associated with LUT fistula development (P<0.001). Among fistula cases, 3.7% of patients (n=8) developed progressive renal insufficiency. Bleeding disorders, subspecialty type, immunosuppressive therapy, smoking, and dialysis were not associated with LUT fistula development.

The incidence of LUT fistula after hysterectomy was lower than previously reported (0.1%-4%), likely because data were limited to 30 days postoperatively. LUT fistula rates decreased over the study period, which may reflect improvements in surgical technique and perioperative detection practices.