UTIs are caused by bacterial colonization of the urinary tract and subsequent inflammation. Sexual intercourse, spermicides, and diaphragms may increase the risk for UTIs, especially when proper hygiene is not maintained. Other factors that increase the risk of developing a UTI include using a urinary catheter, urethral manipulation, frequent pelvic exams, anatomical abnormalities (e.g., urethral stricture, <a href="/conditions/benign-prostatic-hyperplasia/" class="popover" data-tooltip="<div><h6>Benign Prostatic Hyperplasia</h6><p><em>Benign prostatic hyperplasia</em> (BPH) is a condition in which the prostate gland is enlarged and not cancerous. It often leads to lower urinary tract symptoms and is very common in older men (>50 years old).</p></div>">benign prostatic hyperplasia ), kidney transplant, antibiotic use, and diabetes ). [1]

What causes UTIs?

Written by:

Marina Shkayeva

Fact-checked

by:

Graham Walker, Mike Murray

•Last Updated: May 16, 2025

Urinary tract infections are primarily caused by bacterial colonization of the urinary tract, which leads to inflammation. Risk factors include sexual activity, certain contraceptive methods, urinary catheters, anatomical abnormalities, and conditions like diabetes and antibiotic use.

Last Updated:May 16, 2025

UTIs are caused by bacterial colonization of the urinary tract and subsequent inflammation. Sexual intercourse, spermicides, and diaphragms may increase the risk for UTIs, especially when proper hygiene is not maintained. Other factors that increase the risk of developing a UTI include using a urinary catheter, urethral manipulation, frequent pelvic exams, anatomical abnormalities (e.g., urethral stricture, benign prostatic hyperplasia), kidney transplant, antibiotic use, and diabetes).^[1]

References

What causes UTIs? - Examine