What causes a UTI in women? The top 8 reasons

Elizabeth Morrill
Elizabeth Morrill
Published Mar 27, 2023
rolls of white toilet paper on a rose pink background

Key Points:

  1. Urinary tract infections (UTIs) are caused by bacteria that enter the urinary system, usually through the urethra.
  2. The risk of developing a UTI is higher in people with female anatomy. Sexual activity, some kinds of birth control, structural abnormalities, and weakened immune systems can also increase the risk of developing a UTI.
  3. Practicing good hygiene can help reduce the risk of getting a UTI (like always wiping front to back after peeing and urinating after sex). It’s also important to drink plenty of fluids to encourage frequent urination, which helps flush bacteria out of the urinary system.

A urinary tract infection (UTI) is caused by bacteria that grows and spreads in the urinary system, usually through the urethra (the opening where urine comes out).

UTIs are incredibly common, especially among women between the ages of 18-39, but also in children and the elderly. Many different factors can cause this kind of infection, including the medications you take and how much water you drink. The good news? Most people can prevent UTIs by following a few simple steps.

The top 8 potential causes of UTIs

While anyone can develop a UTI, there are certain risk factors that increase the chances of developing one.

The urinary system protects itself against infection by flushing out bacteria through urination. Anything that stops or slows down the flow of urine out of the bladder and urethra can increase the chance that bacteria may grow and spread up the urinary tract.

  1. Having female anatomy: UTIs are especially common in people with female anatomy. More than 50% of all adult women will experience a UTI in their lifetime. That’s because the urethra is closer to the vagina and anus in people with female anatomy. This makes it easier for bacteria from the vagina or anus to enter the urethra. The urethra is also shorter, which makes it easier for bacteria to travel up the urethra to the bladder.
  2. Sexual activity: Having sex increases the risk of developing a UTI. While sex and UTIs are often linked, it’s important to know that you don’t have to be sexually active to get a UTI. Sexual activity does increase the risk of developing a UTI, though. This happens because sex makes it more likely that bacteria from the vagina is introduced to the urethra. Also, some sexually transmitted infections (like herpes, gonorrhea, chlamydia and mycoplasma) can infect the urethra.
  3. Some kinds of birth control: Diaphragms and spermicides can increase the risk of getting a UTI. Some research has also linked unlubricated condoms to UTIs.
  4. Menopause: Lower levels of estrogen after menopause can change the urinary system and increase the risk of UTIs.
  5. Diabetes: Diabetes (and other conditions that impact the immune system) make it harder to fight infections and defend against bacteria that can cause UTIs.
  6. Structural problems: Kidney stones, enlarged prostates or anatomical differences can lead to blockages or other difficulties urinating. When the body can’t regularly flush out bacteria from the urethra through urination, it increases the risk of UTIs.
  7. Pregnancy: Dehydration related to morning sickness can mean you urinate less often. Pregnancy hormones can also change the bacteria in your system. As pregnancy progresses, the weight of the uterus on the bladder and urethra can make it difficult to empty the bladder fully. 
  8. Catheter use: A catheter is a thin, plastic tube that drains urine from the bladder. Catheters can increase the risk of developing a UTI, especially in people who are paralyzed, who have recently undergone a hospital procedure or who have a neurological condition that makes it difficult to control urination.

How to prevent a UTI

You can reduce the chances of developing a UTI by following some simple tips.

  • Drink plenty of fluids, especially water: Staying hydrated ensures that you pee often, which helps to flush bacteria out of your urinary system
  • Wipe front to back: After peeing or having a bowel movement, wipe from front to back only. This helps keep bacteria from the anus and vagina away from the urethra. 
  • Try a different kind of birth control: Diaphragms, unlubricated condoms and spermicides (including condoms treated with spermicide) are linked to more bacterial growth. Talk to your doctor about other forms of birth control.
  • Avoid potentially irritating feminine hygiene products: Douches, deodorant sprays and powders can cause irritation and increase the risk of UTIs.
  • Pee after sex: Use the bathroom after having sex and fully empty your bladder to flush out any potential bacteria. Drinking plenty of water to encourage more urination can help, too.
  • Drink cranberry juice: While the research isn’t 100% clear, some studies suggest that drinking cranberry juice can help protect against UTIs.

UTI treatment you can trust

It’s important to treat UTIs quickly to prevent the infection from spreading or getting worse. If you have symptoms of a UTI – like burning with urination or a frequent urge to urinate – it’s important to talk to a healthcare provider.

Need options for treating your UTI? Dr. B can help with online medical consultations, including prescription UTI antibiotics.


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