Efficacy of Retrograde Fill Vs Spontaneous FIll to Assess Voiding Function

Subjects will be enrolled in the study when presenting to the UNC gynecology outpatient clinic for surgical preoperative evaluation. After surgery, each woman will undergo a voiding trial to assess for urinary retention after surgery. This is currently performed on all patients undergoing surgery involving prolapse or incontinence. At UNC this is usually performed by allowing the bladder to spontaneously fill, then allowing the patient to void and afterward catheterizing the patient to check a postvoid residual ("spontaneous fill" technique). In this study, we will also assess bladder emptying separately by filling the bladder retrograde through the catheter already in place with 300 mL of saline and then removing the catheter and allowing the patient to void ("retrograde-fill" technique). We will determine postvoid residual indirectly by subtracting voided volume from the 300 mL infused volume. No catheterization will be performed with this technique. Both of these techniques will be performed. The order in which the two techniques will be performed will be randomized. We will then compare the outcomes of these two techniques of voiding trials to see if they are equivalent in assessing urinary retention. Of note, the retrograde fill technique is standard at other institutions and is not considered experimental.