To better understand how and why stress incontinence occurs, it is noteworthy to understand the anatomy of the urinary system.
A Pair of Kidneys
These are bean-shaped organs that eliminate liquid waste called urea from the body. Urea is, then, sent in the bloodstream to the kidneys, where it is transported along with water and other wastes in the form of urine. This, in turn, is sent to the bladder and stored therein until it is time to release it from the body.
The Bladder
This urinary organ is the triangle-shaped hollow tissue used as storage of urine in the body. It is found in the lower abdomen and is held in place by ligaments that are attached to other organs and the pelvic bones.
As the bladder is filled with urine, its walls expand to store up to two cups of urine for about 2 to 5 hours. urine, and contract and flatten to empty urine through the urethra. It holds the urine until you allow the release of the fluid when you pee.
The Urethra
This is the tube that connects the bladder to the opening of the body where urine is allowed to pass. When the bladder is full and ready to be emptied, the brain will send neurotransmitters to the bladder muscles to contract and squeeze out the stored fluid through the urethra. This, in turn, will cause the sphincter to open and release the urine.
The Sphincter
As the brain signals the bladder muscle to release the urine, it also signals the sphincter or urethral closure to open to allow the fluid to pass through. The sphincter is a circular muscle that helps keep waste fluid from leaking. It can be characterized as a rubberized bottle cap that tightly closes the opening of the bladder to ensure that no unwarranted leakage will happen.
If these organs, especially the bladder and sphincter, together with the pelvic floor, are functioning well, no uncontrolled leakages should be expected and normal urination occurs. However, if the bladder and urethral closure are damaged or weakened, continence dysfunctions may occur.