Plenty of us know the feeling — the urge to go to the bathroom all the time, yet getting a burning feeling when you try. These are two common symptoms of a urinary tract infection (UTI), which happens when bacteria that don’t usually live within the urinary system enter into a part of it.

By the age of 24, nearly a third of cisgender women will have had a urinary tract infection at least once and 50% of women will experience at least one in their lifetime. An estimated 27% of women who have had a urinary tract infection will have a recurrent episode within six months. 

While there’s no single reason why someone experiences recurrent urinary tract infections, one culprit could be an imbalanced vaginal microbiome.

The vaginal microbiome is a collective term for all of the microorganisms, including bacteria and yeast, that are present within the vagina, and there is a growing body of evidence that indicates the role some of these bacteria play in triggering urinary tract infections. 

So how exactly is the vaginal microbiome related to urinary tract infections? Why do UTIs happen more than once, and what can you do to stop them from recurring? We answer everything you need to know about urinary tract infections and their relationship to the microbiome below. 

What is a urinary tract infection?

A urinary tract infection is an infection that occurs in any part of the urinary system, including the urethra, bladder, ureters, and kidneys. Most UTIs are lower urinary tract infections, affecting the bladder and urethra.

UTI symptoms often include:

  • a strong persistent urge to pee
  • a burning sensation when you pee
  • cloudy or strong-smelling urine
  • pelvic pain.
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What does the vaginal microbiome have to do with UTIs? 

The vaginal microbiome is a complex ecosystem of bacteria, fungi, and more that lives in your vagina. When the vaginal microbiome is in an optimal state, it’s dominated by protective bacteria like Lactobacilli that serve as a critical layer of protection against pathogens (that’s right — some bacteria are your friends). 

But, when something disrupts this balanced environment, the amount of protective bacteria present decreases, allowing disruptive bacteria to come in and make themselves at home.

For some women, recurrent UTIs may be due to bacteria entering the vaginal microbiome, and then traveling into the urethra.

Bacteria responsible for urinary tract infections include:

  • Escherichia coli a.k.a E. coli — these bacteria are responsible for 75% of UTIs in cisgender women
  • Proteus mirabilis
  • Klebsiella pneumoniae
  • Enterococcus faecalis
  • Pseudomonas aeruginosa
  • Streptococcus
  • Staphylococcus
  • Aerococcus
  • Gardnerella vaginalis — while Gardnerella is typically known for its role in bacterial vaginosis (BV), the presence of G. vaginalis in the urethra may also cause a urinary tract infection. 

As with most things in vaginal health, much more research is needed to fully understand the link between bacteria in the vaginal microbiome and recurrent urinary tract infections.

Why do I keep getting UTIs? 

Recurrent UTIs can happen for many reasons. For some women, it's due to the bacteria entering the vaginal microbiome and consistently traveling into the urethra. Women are more prone to urinary tract infections than men because we have a shorter urethra, which allows bacteria easier access to the bladder.

Understanding the full composition of your vaginal microbiome with Evvy’s Vaginal Health Test can help illuminate whether a reservoir of disruptive bacteria in your vaginal microbiome could be contributing to your urinary tract infections. 

On top of disruptions to the vaginal microbiome, other things make it easier to develop a urinary tract infection and make it more likely that it will come back again and again. 

Some of these things include: 


The incidence of urinary tract infections is approximately double for postmenopausal women. Estrogen levels decline during menopause, which then causes a decline in protective bacteria like Lactobacilli.

Menopause can also lead to structural changes and vaginal atrophy which make women more prone to urinary tract infections. This may explain why recurrent urinary tract infections are more common during menopause — as if hot flashes weren’t enough. 

A history of UTIs

Previously having at least one UTI puts you at an increased risk of developing another one. After an infection, small clusters of E. coli can remain within the body and form a biofilm. Biofilms allow bacteria to multiply and make it easier to cause reinfection. 

Vaginal douching 

Vaginal douching, the process of cleaning the vagina using a liquid solution, is still a popular practice. But did you know that douching damages your vaginal microbiome and can make you more prone to recurrent infections?  

Products used for douching contain chemicals that can alter the vagina’s natural pH, leaving the door open for more harmful bacteria to grow. Good news! Along with many of its other superhuman qualities, your vagina is self-cleaning — there is no need for you to wash it using perfumed soaps, gels, or other liquids. 

Birth control

Some forms of birth control that contain spermicide, specifically the compound nonoxynol-9, can work to deplete levels of Lactobacilli (the healthy bacteria in your vaginal microbiome that protect you from pathogens).

For both diaphragms and cervical caps, spermicide is spread onto the surface of the device that is inserted into the vagina. Also, avoid condoms that have spermicide on them since that can harm your vaginal microbiome.

How to prevent urinary tract infections

While evidence is still emerging, there are some things you can do to help prevent urinary tract infections from coming back. And no, chugging cranberry juice isn't the solution to preventing UTIs — sorry!

If you’re going through or have finished menopause...

Vaginal estrogen used in postmenopausal women has been shown to normalize the vaginal flora and prevent UTIs from recurring.

Interestingly, a Cochrane review (aka key research paper) found that only vaginal estrogen, but not oral estrogen, was effective in protecting against UTI recurrence. Talk to your doctor before using estrogen replacement therapy, as it’s not for everyone.

If you’re douching or using anything with spermicide… 

Stop 👏 right 👏 now. 

Avoid behaviors and triggers that increase the risk of developing a urinary tract infection — such as vaginal douching and use of spermicides to reduce your chance of reinfection. 

If you like supplements… 

Probiotics might help prevent future urinary tract infections. Made of living, “good” bacteria, probiotics can help rebalance your microbiome and fight off bad microbes like harmful bacteria, archaea, viruses, or fungi.

Some research suggests that probiotics may be beneficial in preventing recurrent UTIs. As with many other aspects of vaginal health, evidence is limited and much more research is needed. 

Curious about what types of bacteria may be living in your vaginal microbiome and sneaking into your urinary tract?  

Evvy’s at-home vaginal microbiome test identifies all bacteria and fungi present in your vaginal microbiome, including those associated with urinary tract infections. Testing is a great way to monitor your microbiome and symptoms over time, so you can take control of your vaginal health. 


Why do my UTIs keep coming back?

Chronic UTIs can occur for various reasons. In some cases, UTI-causing bacteria may take up residence in the vaginal microbiome and regularly travel into the urethra. Factors such as menopause, a medical history of urinary tract infections, vaginal douching, and certain contraceptives with spermicide can also make it easier to develop a urinary tract infection and increase the likelihood of recurrence. By understanding these factors, you can take steps to reduce the frequency of UTIs. Evvy’s Vaginal Health Test can provide insight into the makeup of your vaginal microbiome, helping you understand if disruptive bacteria could be contributing to your urinary tract infections.

How do I stop recurring urinary tract infections?

You can do some things to help prevent your urinary tract infection from returning. If you're going through or have finished menopause, consider talking to your doctor about vaginal estrogen. It's been shown to normalize the vaginal flora and prevent recurrent UTIs. If you're douching or using anything with spermicide, it's best to stop these behaviors now, as they can increase the risk of frequent UTIs. Additionally, probiotics might help prevent future UTIs by rebalancing your microbiome and fighting off harmful microbes, although more research is still needed to confirm this.

What is the main cause of UTIs in females?

The main reason why women get UTIs is because of bacteria, usually Escherichia coli (E. coli), invading the urinary tract. These bacteria normally live in the gut, but they can sneak into the urinary tract through the urethra. This can happen because of things like anatomy, sexual intercourse, improper wiping (especially back to front), or other behaviors that allow bacteria from the vaginal or anal areas to get into the urethra. Once in the urinary tract, the bacteria can multiply and cause an infection.