3 doctors weighed in:

How does the urinary sphincter work exactly?

3 doctors weighed in
Dr. Tarek Naguib
Internal Medicine - Nephrology & Dialysis
1 doctor agrees

In brief: A muscle contraction

When muscles contract they shorten.
In the sphincter, the muscles are laid in a circular fashion around the opening that passes urine at the base of the baldder. When they contract, they shorten, thereby tightening the opening in the middle and shutting flow. The sphincter is under the control of both voluntary and involuntary nervous systems. That explains incontinence when someone is very scared.

In brief: A muscle contraction

When muscles contract they shorten.
In the sphincter, the muscles are laid in a circular fashion around the opening that passes urine at the base of the baldder. When they contract, they shorten, thereby tightening the opening in the middle and shutting flow. The sphincter is under the control of both voluntary and involuntary nervous systems. That explains incontinence when someone is very scared.
Dr. Tarek Naguib
Dr. Tarek Naguib
Thank
Dr. Frances Dyro
Neurology

In brief: Neurologically

The urinary or urethral sphincter encircles the lower part of the bladder and the tubing (urethra) that carries the urine out of the body.
It is composed of muscle that controls the holding back of urine and relaxes when we wish to pee. This cycle is controlled by centers in the spinal cord and in the brain. This muscle may be weakened by aging or pregnancy causing stress incontinence.

In brief: Neurologically

The urinary or urethral sphincter encircles the lower part of the bladder and the tubing (urethra) that carries the urine out of the body.
It is composed of muscle that controls the holding back of urine and relaxes when we wish to pee. This cycle is controlled by centers in the spinal cord and in the brain. This muscle may be weakened by aging or pregnancy causing stress incontinence.
Dr. Frances Dyro
Dr. Frances Dyro
Thank
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