An Introduction to Urinary Incontinence.

Cover Story:
BioStim™ for Pelvic Floor Strengthening'
Dorothy Stevens RN. RM. Continence Consultant & Practitioner.

Therapy Closeup:
Pelvic Floor Strengthening

Bits n' Pieces:
Bio Notes:
Dorothy Stevens

User Profiles:
Those with incontinence tell their stories.

The Fact Files:
Scientific research in support of Electrical Stimulation for urinary incontinence.

Urine is a by-product of the kidneys, whose function is to filter the blood of excess fluids, salts, and other trace elements. The healthy adult produces around 1500 ml of urine per day, but there is considerable variation from day to day. The volume of urine produced depends on fluid intake, and the amount of fluid lost in imperceptible evaporation from the breath and the skin, and by overt sweating, as well as fluid lost in the bowel motions.

Urine produced by the kidneys flows down two muscular tubes called ureters to the bladder - where it is stored, ready to be expelled. Urine actually leaves the body by a single tube called the urethra.

Urine can only escape from the bladder when the pressure inside the bladder is higher than the pressure which keeps the urethra closed. Normally, this only occurs when the bladder contracts in the voluntary act of urination. Normally the urethra is kept closed by the sphincter muscles which encircle it. If, for any reason, these sphincter muscles are weak, urine can leak out of the bladder when its internal pressure is increased - for example during coughing, sneezing, etc.. Leakage of urine under these circumstances is called stress incontinence, and is particularly common in pregnant women and those who have had 4 or more children. Because it is due to sphincter muscle weakness, it is amenable to correction by strengthening these muscles.

The pelvis has two basic groups of muscles - the levators (which are the true pelvic floor muscles), and the sphincter muscles. The levators act like a sling which supports the organs in the pelvis. While the sphincter muscles form a ring around the external openings, and act as control valves to prevent leakage from the bladder and the bowel.

During childbirth, the levators act as a guide for the head of the baby, turning and directing it toward the birth canal and vagina. At a later stage in the delivery, these muscles are considerably stretched as the baby's head and body are passed through to the outside. The bigger the baby's head, there is more stretching that must occur. If the delivery is very rapid the muscles may be torn, bruised and injured. The more babies, the greater are the chances of damage to the pelvic floor musculature. In addition, partial damage to the nerve supply of these muscles can occur during childbirth and results in further weakness.

Birth trauma of this kind, and changes to the muscles secondary to menopause and aging, are the commonest causes of pelvic floor and sphincter weakness - which is what causes urinary incontinence. Once there is weakness in these control mechanisms, hormonal changes that occur during periods can exacerbate the leakage problem.

Urinary Incontinence has been defined as the failure of control of the urethral sphincter, with constant or frequent involuntary passage of urine.

Other than stress incontinence, the other most common type is urge incontinence - in which there is urine leakage associated with the desire to void.