Causes Of A Urinary Tract Infection

August 29, 2023

Urinary tract infections (UTIs) are incredibly common, especially among women. They are also the second most common infection after the common cold and affect over fifty percent of women during their lives. While these infections don't always cause symptoms, they can cause pain, burning while peeing, and an urgent need to go to the bathroom. UTIs can also spread from the bladder to the kidneys and even the blood, and lead to serious complications if they are left untreated. Once an individual has had a single UTI, they are more likely to get another. Some women even have chronic urinary tract infections. There are many possible causes of a urinary tract infection, but the following are most common.


Many diseases and medical conditions actually increase the risk of developing a UTI, and one of the most common is diabetes. Individuals with diabetes that is not well controlled are twice as likely to develop a urinary tract infection because the sugar in urine promotes the growth of harmful bacteria. Kidney stones can also make a urinary tract infection more likely. According to one study, eight percent of individuals with kidney stones also had a UTI. Many of the symptoms of kidney stones also mimic the symptoms of a urinary tract infection, such as pain while peeing and an urgent need to go to the bathroom.

There may be other conditions that can make a UTI more likely, such as having a shorter urethra or other urinary tract abnormalities or having a 'lazy bladder' that does not empty fully. Any disease that affects the immune system, which is the body's defense against infection, may also raise the risk of a UTI.


Dehydration can affect the entire body, even when someone is only slightly dehydrated. Failing to get enough fluids stresses the immune system, making it harder to attack bacteria in the body. Staying well-hydrated also helps flush out bacteria that multiply in the urinary tract.

The bladder is the part of the urinary system that acts as a collection container for urine until individuals use the restroom. When bacteria enter the bladder through the urethra, they are essentially sitting there and waiting until the individual urinates. This is the ideal place for bacteria to multiply and infect the bladder walls. When individuals pee, they aren't just flushing out urine. In fact, they are also flushing out bacteria in the bladder. Dehydration can suppress the immune system and allow the bacteria more time to multiply in the bladder until it causes an infection.

Wiping The Wrong Way

How someone wipes can affect whether or not they get a UTI. Wiping the wrong way, which means back to front, can bring bacteria like E. coli from the rectum and fecal matter into the urethra. E. coli, which lives in the intestines, is one of the most common causes of urinary tract infections. Women are already more likely to develop UTIs than men because their urethras are closer to the anus, and women also have shorter urethras than men, which makes it easier for bacteria to travel into the bladder once they reach the opening of the urethra. The correct way to wipe is from front to back, even after peeing but especially after a bowel movement.


Intercourse is a common trigger for urinary tract infections in women as it introduces bacteria into the urinary tract. During sex, bacteria from the genitals and anus come into contact with the urethra. This allows bacteria to enter the bladder, urethra, and even the kidneys and result in an infection. About eighty percent of women with a UTI have had sex within the last day. Frequent sex with one or multiple partners, sex with a new partner, and an increased number of sex partners all increase this risk.

However, preventing a urinary tract infection doesn't need to mean abstinence. There are several ways to lower the risk of getting a UTI from sex. Washing up before sex can reduce the bacteria on the genitals of both partners. Peeing before and right afterward can help flush out bacteria that enter the urinary tract. Avoiding the use of spermicide or a diaphragm as birth control may also reduce this risk.

Medications Like Birth Control

Birth control is a common trigger of urinary tract infections, although not all contraceptives cause UTIs. Diaphragms, condoms, intrauterine devices (IUDs), and medications like birth control may make you more prone to a urinary tract infection. An IUD can increase the risk of a UTI for several reasons. One study found twenty-five percent of IUD users had trigone congestion. The bladder trigone is a region of the bladder that is responsive to the expansion of the bladder as it fills and triggers the brain to know you need to urine. Congestion refers to dilation of the vessels supplying blood to this region. IUDs can also form bacterial biofilms in some cases that may trigger an infection. Oral contraceptives have also been linked to an increased risk of a urinary tract infection, so if individuals have recurring urinary tract infections, switching to a different form of birth control may be recommended.

Bladder Infections

The urinary system has four major parts. The kidneys act as the body's filter, removing waste products from the blood. The ureters connect the kidneys to the bladder. The bladder stores urine for disposal. The urethra is the final passage for moving liquid waste from inside to outside the body. When bacteria, especially E. coli, find their way into any of these areas, a urinary tract infection can be the result. This is especially a problem for women as anatomically they have a shorter, interior urethra making it easier for bacteria to enter the bladder from the outside. Bacteria are often transferred through diaphragm use, tampon use, unhygienic wiping, and sexual intercourse.

Use Of A Catheter

The use of a catheter is the most common cause of a urinary tract infection for men. A catheter is a tube used to assist in emptying the bladder when an individual has difficulty doing so due to health conditions such as an enlarged prostate. Unfortunately, bacteria can be transferred to the urinary tract and directly into the bladder by traveling along the catheter. Catheter use is safe when basic precautions are taken. The catheter should always be kept in its sterile container when not in use. Whoever is inserting the tube must wash their hands before the insertion as well as after. The skin around the insertion point should be sterilized with alcohol before the procedure. Catheterization should not be used as a convenience, but only when it is truly necessary.

Heavy Antibiotic Use

The most common way to deal with a urinary tract infection is through the prescription of antibiotics. However, there is a danger of worse infections with heavy antibiotic use. Antibiotics will not necessarily cause a UTI, but heavy use increases the likelihood bacteria will become resistant to antibiotics. For this reason, many doctors do not immediately prescribe antibiotics when bacteria are found in a urine sample. Bacteria may live in the urinary tract without causing problems. Instead, they will often wait to see if there is a positive test for bacteria along with symptoms of a UTI before administering any antibiotics. They will also minimize the course of antibiotics and use the lowest effective dosage as much as possible to avoid potential resistance.

Incomplete Bladder Voiding

Incomplete bladder voiding is a frustrating experience as the patient will have frequent urges to urinate, though they are often not productive. The retention of liquid in the bladder also creates a climate hospitable for bacteria growth. There are many reasons an individual may be faced with incomplete bladder voiding. For men, it is often a physical blockage. A kidney stone or bladder stone may prevent the ability to fully empty the bladder. An enlarged prostate can make it difficult to push urine through the urethra. For women, the physical pressure of a growing fetus on the bladder can make full urination difficult during pregnancy. Reduced levels of estrogen after menopause can weaken the urinary tract, which can lead to incomplete voiding.

Bowel Incontinence

Bowel incontinence is a common cause of urinary tract infections, especially in patients who are unable to care for themselves. Due to the differences in anatomy, women are more likely to have a UTI for this reason. However, if incontinence is not addressed quickly, it can be a serious issue for men as well. There are a host of bacteria that live happily in the digestive tract without issue. If a patient is sitting in feces for any length of time, bacteria can make their way to the urethra, and a urinary tract infection may follow. For this reason, caregivers at homes, hospitals, and nursing facilities must check their patients frequently and make sure they are clean and comfortable.

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