In Children
Urination, or voiding, is a complex activity. The bladder is a balloonlike muscle that lies in the lowest part of the abdomen. The bladder stores urine, then releases it through the urethra, the canal that carries urine to the outside of the body. Controlling this activity involves nerves, muscles, the spinal cord and the brain.
The bladder is made of two types of muscles: the detrusor, a muscular sac that stores urine and squeezes to empty, and the sphincter, a circular group of muscles at the bottom or neck of the bladder that automatically stay contracted to hold the urine in and automatically relax when the detrusor contracts to let the urine into the urethra. A third group of muscles below the bladder (pelvic floor muscles) can contract to keep urine back.
A baby's bladder fills to a set point, then automatically contracts and empties. As the child gets older, the nervous system develops. The child's brain begins to get messages from the filling bladder and begins to send messages to the bladder to keep it from automatically emptying until the child decides it is the time and place to void.
Failures in this control mechanism result in incontinence. Reasons for this failure range from the simple to the complex.
Incontinence happens less often after age 5: About 10 percent of 5-year-olds, 5 percent of 10-year-olds, and 1 percent of 18-year-olds experience episodes of incontinence. It is twice as common in girls as in boys.
Read more about this topic: Urinary Incontinence
Famous quotes containing the word children:
“He hangs in the hall by his black cravat,
The ladies faint, and the children holler:
Only my Daddy could look like that,
And I love my Daddy like he loves his Dollar.”
—William Jay Smith (b. 1918)
“In the planning and designing of new communities, housing projects, and urban renewal, the planners both public and private, need to give explicit consideration to the kind of world that is being created for the children who will be growing up in these settings. Particular attention should be given to the opportunities which the environment presents or precludes for involvement of children with persons both older and younger than themselves.”
—Urie Bronfenbrenner (b. 1917)