OBJECTIVE: The aim of this study was to determine the effect of preoperative oral phenazopyridine on short-term voiding dysfunction in patients undergoing a retropubic midurethral sling. METHODS: We conducted a retrospective cohort study in subjects undergoing a retropubic midurethral sling comparing those who received preoperative oral phenazopyridine with those who did not. We included all women who underwent a retropubic midurethral sling without concomitant procedures under general anesthesia at our institution. Slings were placed by either suprapubic or transvaginal approach, per surgeon's preference. Demographics and intraoperative data on preoperative dose of phenazopyridine and medications linked to voiding dysfunction were captured. RESULTS: One hundred seventy-four subjects were identified. Twenty-five subjects failed to meet inclusion and exclusion criteria and were excluded, and 149 subjects comprised the final groups. Eighty-two subjects (55.03%) received phenazopyridine, and 67 (44.97%) did not. Most subjects received a 200-mg dose (97.6%). Except for surgical approach, both groups receiving and not receiving phenazopyridine had similar demographic characteristics. Eighty-eight percent of the subjects who received phenazopyridine passed the voiding trial versus 73.1% (odds ratio, 2.98; 95% confidence interval, 1.23-7.17). After adjusting for medications, estimated blood loss, number of trocar passages, or bladder perforation, the patients receiving phenazopyridine were still more likely to pass the postoperative voiding trials compared with those who did not (odds ratio, 2.97; 95% confidence interval, 1.10-7.98). CONCLUSIONS: Our findings suggest that the preoperative administration of phenazopyridine may improve postoperative voiding function after a retropubic midurethral sling. Additional prospective trials are needed to confirm this finding.