['We evaluated the incidence of cryptorchidism and inguinal hernias in patients with posterior urethral valves, and compared characteristics in patients with and without cryptorchidism or inguinal hernia.', 'A total of 200 patients with posterior urethral valves treated between 1953 and 2003 were identified from a hospital database. Patient records were retrospectively reviewed. The state of testicular descent and the presence of inguinal hernias were recorded in 192 patients. Patient characteristics were analyzed.', 'Of 192 patients 31 (16%) had cryptorchidism, which was bilateral in 9 (29%). A total of 21 patients (11%) had inguinal hernias that were not associated with cryptorchid testes. The patients with cryptorchidism, and to some extent the patients with hernias, appeared to have a more severe form of posterior urethral valves than those without cryptorchidism. At the time of diagnosis the median serum creatinine concentration was 100 mumol/l (range 38 to 460) in boys with cryptorchidism and 87 (14 to 593) in boys without cryptorchidism (p = 0.131). At 6-month followup the median serum creatinine levels were 90 mumol/l (range 31 to 573) in patients with cryptorchidism and 45 (19 to 504) in patients without cryptorchidism (p = 0.006). Cryptorchidism was also more common in cases diagnosed neonatally compared to those diagnosed at a later age (14 of 52 patients, 27% vs 14 of 112, 12.5%, respectively, p = 0.027).'] Are posterior urethral valves often associated with cryptorchidism and inguinal hernias?