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Get answers to your Urinary Incontinence / Urogynecology questions.
Dr. Johnson’s Bio | Q&A Archive
Loss of bladder control; Uncontrollable urination; Urination - uncontrollable; Incontinence - urinary
Urinary (or bladder) incontinence is when you are not able to keep urine from leaking from your urethra, the tube that carries urine out of your body from your bladder. It can range from an occasional leakage of urine, to a complete inability to hold any urine.
The three main types of urinary incontinence are:
Bowel incontinence, a separate topic, is the inability to control the passage of stool.
Incontinence is most common among the elderly. Women are more likely than men to have urinary incontinence.
Infants and children are not considered incontinent, but merely untrained, up to the time of toilet training. Occasional accidents are not unusual in children up to age 6 years. Young (and sometimes teenage) girls may have slight leakage of urine when laughing.
Nighttime urination in children is normal until the age of 5 or 6.
NORMAL URINATION
Normally, the bladder begins to fill with urine from the kidneys. The bladder stretches to allow increasing amounts of urine.
The first urge to urinate occurs when around 200 mL (just under 1 cup) of urine is stored in the bladder. A healthy nervous system will respond to this stretching sensation by alerting you to the urge to urinate, while also allowing the bladder to continue to fill.
The average person can hold around 350 to 550 mL (more than 2 cups) of urine. Two muscles help control the flow of urine:
When it is time to empty the bladder, the bladder wall (detrusor) muscle contracts or squeezes to force urine out of the bladder. Before this muscle squeezes, your body must be able to relax the sphincter to allow the urine to pass out of the body.
The ability to control urination depends on having normal anatomy, a normally functioning nervous system, and the ability to recognize and respond to the urge to urinate.
Causes include:
Incontinence may be sudden and temporary, or ongoing and long-term. Causes of sudden or temporary incontinence include:
Causes that may be more long-term:
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Holroyd-Leduc JM, Tannenbaum C, Thorpe KE, Straus SE. What type of urinary incontinence does this woman have? JAMA. 2008;299:1446-1456.
Rogers RG. Clinical practice: urinary stress incontinence in women. N Engl J Med. 2008;358:1029-1036.
Shamliyan TA, Kane RL, Wyman J, Wilt TJ. Systematic review: randomized, controlled trials of nonsurgical treatments for urinary incontinence in women. Ann Intern Med. 2008;148:459-473.
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