As mentioned above, sexual activity is the most commonly reported cause of UTIs. During sexual activity, bacteria, most commonly e. coli, are transferred from the vagina, anus, or sexual partner to the urinary tract. Any form of sexual activity physically moves or transplants bacteria to the urethra, where they can travel up and establish an infection. The longer the time the bacteria have to travel up the urinary tract, the more likely an infection is. This is why peeing after sex is always a good idea. However, this is not always enough to keep bacteria from traveling through the urinary tract.

Sweat and moisture allow bacteria to move around when exercising, which can transfer them to the urethra. If the clothes worn while exercising are not breathable, this typically increases moisture and makes bacterial travel more likely. Exercising and then not showering for an extended period of time will allow bacteria more time to travel before washing.

Our first line of defense against bacteria entering the urinary tract is physically flushing them out via urination. The more time (the longer we hold it) that we allow bacteria to travel up the urinary tract, the higher the risk of UTI. This is also why people with certain professions, like teachers, nurses, and more, who may not be able to use the bathroom as frequently as they’d like, may experience higher rates of UTIs.

Many women report getting UTIs cyclically immediately following their period. Like with sexual activity, the vaginal ecosystem plays an important role. Pathogenic bacteria thrive at a higher vaginal pH and are normally kept in check at a lower pH. Hormones are also changing as estrogen production dips prior to menstruation. This can make the urinary tract temporarily more vulnerable to infection as bacteria travel from the vagina to the urethra. Increased moisture can also play a part, and research has shown that more frequent changing of feminine hygiene products during menstruation can decrease the risk of UTIs.

During menopause, estrogen production declines. This leads to big changes in the vaginal microbiome and a decline in lactobacilli (good bacteria). With a decrease of good bacteria, the vaginal microbiome could become dominated by pathogenic bacteria, even E. Coli. These bacteria are then more likely to travel to the urinary tract. While not necessarily a “cause” of UTIs, menopause, like periods, increases the risk of UTIs from all triggers. Menopausal and postmenopausal UTIs are still often triggered by certain activities, like sex and many other activities. With more pathogenic bacteria around, the more likely these triggers are to cause UTIs.

Similar to when not urinating for long periods, taking airplane rides and sitting for a long time at once may increase UTI risk. Travel can also be stressful and tiring, which may also contribute to the association between traveling and UTIs. Typical hygiene routines may also be disrupted when traveling, which could lead to a higher likelihood of bacteria getting into the urinary tract. If you’re camping, for example, you’re likely not able to shower or bathe with the regularity you’re used to.