How well do you know your own body? To help you understand your body and the problems you may encounter, we are looking at the urinary system.
- The urinary tract is responsible for the production, storage and passing of urine. It includes the kidneys, ureters (upper urinary tract), bladder and urethra (lower urinary tract).
- The two kidneys lie at the back of the abdomen, behind your 12th and 13th rib. They produce urine by ‘filtering’ unwanted substances from the blood. The urine produced passes out of the kidneys, down both ureters and into the bladder, where it is stored.
- The bladder fills with urine over 3–4 hours. As it fills, you become increasingly aware of the need to pass urine (called the ‘urge sensation’). During urination, urine passes from the bladder down the urethra to the outside. This involves simultaneous relaxation of the muscles around the urethra and contraction of the muscles of the bladder.
- Semen is made in the testes (testicles) and passed up two tubes (called the vas deferens) to be stored in the seminal vesicles behind the prostate. At ejaculation, the bladder neck closes and semen passes down the urethra and out through the penis.
- The prostate is a small gland just below the bladder that fits around the urethra rather like a collar It resembles a walnut. The prostate produces a fluid that forms part of the semen.
- In men over 40, the prostate often enlarges gradually and presses on the urethra causing obstruction. This can make it difficult to pass urine and you may be unable to empty your bladder completely. You may also feel the need to pass urine more often and more urgently.
- Women are more likely to suffer from urinary tract infections (UTIs) than men for many reasons, one may be because the female urethra is much shorter. Emptying your bladder shortly after sex may help to avoid UTIs.
- After childbirth, one out of three women report leaking small amounts of urine when they cough or sneeze. This is called ‘stress incontinence’ and occurs when the pelvic floor muscles have been weakened by the passage of the baby down the birth canal (vagina). Performing pelvic floor exercises may help strengthen the muscles and stop urine leaking out.
- The flow of urine may be blocked or obstructed if the urethra is narrowed by scar tissue a dropped bladder or uterus (prolapse) or the muscles of the urethra fail to relax. However, this is uncommon.
First published on: embarrassingproblems.com
Reviewed and edited by: Dr Diane Newman
Last updated: October 2020