Ninety-two patients with preoperative sterile urine undergoing colposuspension or vaginal repair operation for stress urinary incontinence and/or genital descensus were randomized to either suprapubic or transurethral postoperative catheter drainage. The prevalence of significant bacteriuria on the fifth postoperative day was statistically significantly lower when using suprapubic catheter (20.8%) than with transurethral catheter drainage (45.5%). This applied especially to colposuspension. The rate of postoperatively impaired bladder emptying also tended to be reduced when using suprapubic catheter. At follow-up after one year, postoperative bacteriuria was closely correlated to increased rates of both clinical cystitis and asymptomatic significant bacteriuria. Thus it is recommended to use suprapubic bladder drainage not only after colposuspension but also after vaginal repair in an effort to avoid an increased risk of urinary infections.