A concept of urinary continence.

Urinary continence exists provided urine has no other outlet than through a section of the urethra where pressure at all times, except during normal micturition, is higher than it is in the bladder. Closure pressure, the difference between maximal intra-urethral pressure and simultaneously existing bladder pressure, normally remains above zero also during vigorous physical stress, such as coughing, mainly because intraabdominal pressure is readily transmitted not only to the bladder, but also to the upper urethra, which is above the urogenital diaphragm.