Bladder function is often compromised in juvenile patients with posterior urethral valves (PUV). In infancy, such abnormal bladder function is characterized by low compliance or overactivity, but later in life the bladder tends to become oversized and empties poorly. Polyuria, which is often associated with renal failure as well as secondary changes in the bladder neck, also has an effect on bladder function. Perhaps as a consequence of these contributing factors, toilet training is often delayed in children with PUV. Adults who were treated for PUV as a child tend to experience lower urinary tract symptoms at a rate twofold to threefold higher than healthy men. Furthermore, these adult patients with PUV might have risk factors for sexual and fertility dysfunctions later in life, such as cryptorchidism, renal failure and abnormal posterior urethra. However, despite the high incidence of these risk factors, sexual function and fertility seems to be normal in most patients.