What Causes UTIs?

What Causes UTIs

Urinary tract infections (UTIs) typically occur when bacteria enter the urinary tract through the urethra and begin to multiply in the bladder. Although the urinary system is designed to keep out bacteria, these defences sometimes fail. When that happens, bacteria may take hold and grow into a full-blown infection in the urinary tract.


For a lot of us, UTIs are caused by specific activities that cause bacteria to enter the urinary tract through the urethra. For example, this may occur when wiping your bottom or having sex, but often it’s not clear why it happens. However, UTIs aren’t always caused by specific activities. Sometimes, UTIs seem to come out of nowhere and once we get just one UTI, our likelihood of getting another increase. Biofilm is a tool that UTI-causing bacteria use to hide from both your immune system and antibiotics, waiting for a good time to release and start a recurrent UTI.  That’s why some UTIs seem to come out of nowhere, unlinked to specific activities.

Risk factors:

The following may increase your risk of getting a UTI:

  • Being in a nursing home or hospital.
  • Menopause: Estrogen is essential for the production of “good” bacteria to fight off “bad bacteria”.
  • Blockages in the Urinary Tract: Kidney stones or an enlarged prostate (men) can trap urine in the bladder and increase the risk of UTSs.
  • Difficulty emptying your bladder fully typically caused by an enlarged prostate that presses on the bladder.
  • Urinary Tract Abnormalities: Some babies are born with problems that stop the urine travelling properly though the urinary system.
  • Weakened or Suppressed Immune system (e.g. from diabetes, HIV, or chemotherapy for example).
  • A recent medical procedure on the urinary tract.
  • Catheter use: People who can’t urinate on their own and use a tube (catheter) to urinate have an increased risk of UTIs. This may include people who are hospitalized, people with neurological problems that make it difficult to control their ability to urinate and people who are paralyzed.
  • Female anatomy. A woman has a shorter urethra than a man does, which shortens the distance that bacteria must travel to reach the bladder.
  • Pregnancy: The uterus sits directly on top of the bladder, and as it grows, its increased weight can block the drainage of urine from the bladder.
  • Genetics Some people have cells with toll-like receptors that bacteria can bind to more easily.
  • Sexual Intercourse.

Who gets UTIs?

UTIs happen much more frequently in women than in men. The ratio is 8:1. This means that for every eight women who have UTIs, only one man does. Furthermore, women have a 1-in-2 chance of developing a UTI in their lifetime and many women experience more than one infection during their lifetimes. Women may be more likely to get UTIs because their urethra is shorter than a man’s and is much closer to their anus.  The risk of developing a UTI increases with age for both men and women alike.


A woman has a 50% chance of experiencing a UTI in her lifetime, and one in ten women have 3 or more UTIs a year.*

*Amy B. Howell, Henry Botto et al. BMC Infectious Diseases 2010, 10:94

Women are more likely to develop a UTI if they:

  • Are sexually active: This is because having sex can irritate the urethra. When this happens it allows bacteria to travel more easily though the urethra and into the bladder.
  • Use a diaphragm as contraception: The diaphragm can put pressure on the bladder and stop it from emptying properly.
  • Develop an irritation to spermicide used on condoms: Some women develop a vaginal irritation from spermicide, making the area more vulnerable to infection.
  • Are pregnant: Hormonal changes during pregnancy make women more vulnerable to UTIs.
  • Are in Menopause: When levels of the hormone oestrogen decline, changes in the urinary tract occur and women may become more vulnerable to developing a UTI.


Consider URIEXO® if you are prone to UTIs – URIEXO® is a Natural Health Product licensed by Health Canada that is clinically proven to stop UTIs before they start.

Symptoms of UTIs: The symptoms of UTIs vary depending on the location of the infections.  Learn how to recognize these symptoms.

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Medical Complications: While milder UTIs will often go away on their own without treatment, you shouldn’t avoid seeing a doctor if the symptoms persist for more than a couple of days. Learn more about why and when you should see your doctor.

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UTI Prevention: Anyone who has ever had a urinary tract infection (UTI) knows full well how frustrating and uncomfortable they can be. Getting ahead of UTIs, with these UTI prevention tips, can help you prevent UTIs.

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Treatment of UTIs: Learn more about your options to both treat and prevent recurrent UTIs.

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Antibiotic Resistance: The growing concern over the risk of antibiotic resistance is the primary reasons most healthcare practitioners are now turning towards non-antibiotic approaches to prevent recurrent UTIs. Learn more about using antibiotics wisely!

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