Men get urinary tract infections when bacteria enter the urethra and travel upward into the bladder. While UTIs are far less common in men than in women, they do happen, and the causes shift significantly with age. In younger men, sexual activity and structural abnormalities are the usual culprits. After age 50, an enlarging prostate becomes the dominant risk factor.
Why Men Get Fewer UTIs Than Women
The male urethra is about 20 centimeters (roughly 8 inches) long, compared to only 3 to 4 centimeters in women. That extra distance makes it much harder for bacteria to reach the bladder. The prostate gland also produces secretions with antimicrobial properties that help keep bacteria in check. These two built-in defenses mean most healthy young men will never experience a UTI.
When a man does get one, it usually signals that something is making it easier for bacteria to gain a foothold, whether that’s a physical obstruction, a medical device, or a weakened immune system.
The Bacteria Behind It
The most common bacteria involved are the same ones that live in your intestines. E. coli is responsible for about 25% of male UTIs, with other gut bacteria like Proteus and Providencia accounting for much of the rest. These organisms spread from the skin around the anus to the urethra and then climb upward into the bladder. In some cases, bacteria transmitted through sexual contact, including gonorrhea and chlamydia, cause infections in the urethra specifically.
Upper tract infections, which reach the kidneys, typically happen one of two ways: bacteria travel upward from an already-infected bladder, or bacteria circulating in the bloodstream settle in the kidney.
Enlarged Prostate: The Biggest Risk After 50
The prostate gland sits right where the urethra exits the bladder. In younger men it’s roughly the size of a walnut, but it grows steadily with age. By the time many men reach their 50s and 60s, the prostate has enlarged enough to squeeze the urethra and partially block urine flow. This condition, called benign prostatic hyperplasia (BPH), is extremely common.
The problem isn’t the enlarged gland itself. It’s what happens when you can’t fully empty your bladder. Urine that sits in the bladder becomes a breeding ground for bacteria. The longer it pools, the more opportunity bacteria have to multiply and establish an infection. BPH can also put enough pressure on the bladder to let infections travel upward to the kidneys.
Sexual Activity
Sex can increase UTI risk in men, though it doesn’t directly cause one. Intercourse can push bacteria toward or into the urethra, giving them a head start on the journey to the bladder. UTIs are not sexually transmitted infections, but the physical mechanics of sex create an opening for bacteria that are already present on the skin. Anal intercourse carries a higher risk because it increases exposure to intestinal bacteria.
Catheters and Medical Procedures
Any instrument that enters the urinary tract can introduce bacteria. Urinary catheters are one of the leading causes of UTIs in hospitalized men. The longer a catheter stays in place, the greater the risk. Other factors that compound the danger include older age, diabetes, a weakened immune system, and catheter placement done outside of an operating room. Even after removal, the irritation left behind can make infection more likely in the short term.
In nursing home settings, men without catheters have lower rates of both bacterial colonization and symptomatic UTIs compared to men using continuous external catheters.
Kidney Stones and Other Blockages
Anything that blocks the normal flow of urine raises infection risk. Kidney stones can lodge in the ureters (the tubes connecting the kidneys to the bladder), causing urine to back up and creating conditions where bacteria thrive. There’s also a specific type of stone, called a struvite stone, that actually forms in response to a UTI. These stones can grow quickly and become quite large, sometimes causing a cycle of recurring infections.
Urethral strictures, which are narrow spots in the urethra caused by injury or scarring, create similar problems by preventing complete bladder emptying.
Diabetes and Weakened Immunity
Diabetes is a well-established risk factor for UTIs in men. High blood sugar impairs the immune response and changes the environment inside the urinary tract in ways that make it easier for bacteria to colonize and multiply. The combination of reduced immune function and sugar-rich urine essentially rolls out the welcome mat for infection.
Other conditions that suppress the immune system, including HIV, chemotherapy, and long-term steroid use, similarly increase vulnerability.
What a Male UTI Feels Like
Lower tract infections (bladder and urethra) typically cause a burning sensation during urination, a frequent and urgent need to pee, and cloudy or strong-smelling urine. You might also feel pressure or discomfort in the lower abdomen. Some men notice blood in their urine.
Upper tract infections that reach the kidneys are more serious. They often bring fever, chills, nausea, and pain in the back or side. Because male UTIs frequently involve the prostate as well, symptoms can overlap with prostatitis: deep pelvic pain, difficulty starting urination, or a weak urine stream. A urine culture is the standard tool for confirming the diagnosis and identifying which bacteria are responsible, which helps determine the right treatment.
Reducing Your Risk
The CDC recommends a few straightforward habits: urinate after sexual activity to flush out any bacteria that may have entered the urethra, stay well hydrated so you’re urinating regularly throughout the day, and take showers instead of baths. Avoid sprays or powders in the genital area, which can irritate the urethra and create an easier path for bacteria.
For men with BPH or recurring infections, fully emptying the bladder matters most. That may mean taking extra time when urinating, double voiding (waiting a moment after finishing and trying again), or working with a doctor to manage prostate enlargement. Men prone to struvite kidney stones benefit from maintaining good urine flow and urinating frequently to keep bacteria from building up.