Eighty-six abacteriuric women with chronic urologic complaints were studied to determine the relationship of Chlamydia trachomatis, Mycoplasma hominis, and Ureaplasma urealyticum to their symptoms or diagnoses. All patients had urethral scrape specimens for isolation of the three organisms as well as a detailed urologic history and urodynamic evaluation. Thirty-three of 86 patients (38%) had positive urethral ureaplasma cultures; seven had concurrent M. hominis isolation. No patient had M. hominis as the only urethral isolate and none had a positive C. trachomatis culture. There were no significant differences in urologic symptoms or in urodynamic diagnoses between Ureaplasma culture-positive and culture-negative subjects. It was also found that colonization of the urethra with Ureaplasma decreased with increasing age and with hypoestrogenism.