The effects of sex hormones on bladder function have been evaluated in adult females, especially in regard to postmenopausal incontinence and bladder irritability syndromes. These have not been investigated in children in regard to urodynamic findings. An intersex patient whose bladder is under the influence of androgens is a natural model to investigate the effects of male sex hormones on bladder function in females. To evaluate the urodynamic findings and clinical symptoms in a group of intersex patients and to determine how androgens influence bladder function in female children, clinical and urodynamic records of 12 intersex patients with adrenogenital syndrome were investigated retrospectively The mean age was 9 +/- 5.7 years (1.5-18) and the mean follow-up period was 5.1 +/- 4.4 years (1-12). Congenital adrenal hyperplasia (CAH) was present in all cases. Only 3 patients had urinary symptoms and incontinence, but these findings did not correlate with their urodynamic findings. None of the patients required medications for their urinary symptoms. Nine are still being treated medically by the pediatric endocrine team with hydrocortisone for CAH. The upper urinary tract was found to be normal with no hydronephrosis. The mean bladder capacity (269 +/- 122 ml) was lower (86.7%) than the estimated capacity for age. The mean compliance was 20 +/- 13.7 ml/cmH(2)O. No unstable detrusor contractions were encountered. The most remarkable finding was this reduced bladder capacity of androgenized female patients for age, which shows the antagonistic effect of androgens on bladder urodynamics in females.