A urethral stricture is an abnormal narrowing of the urethra, the tube that carries urine from the bladder out of the body. It happens when scar tissue builds up in or around the urethral wall, physically squeezing the channel smaller and making it harder to urinate. The condition affects roughly 0.6% of men and becomes significantly more common after age 55.
How Scar Tissue Narrows the Urethra
The urethra in men is surrounded by a layer of spongy tissue. When that tissue is injured, whether from the inside or outside, urine can leak into the surrounding spongy layer or the tissue itself gets directly damaged. Either way, the body responds with inflammation and eventually lays down fibrous scar tissue. Over time, this scar tissue contracts and shrinks, compressing the urethral opening from the outside in. In severe cases, the spongy tissue can be completely replaced by scar, turning a flexible tube into a rigid, narrowed pipe.
The narrowing can happen anywhere along the urethra and can range from a short, pinpoint constriction to a long segment of scarring. The location and length of the stricture matter a great deal when it comes to choosing treatment.
Common Causes
Strictures develop from anything that injures the urethra. In high-income countries, the most frequent cause is iatrogenic injury, meaning it results from a medical procedure. Catheter placement, prostate surgery, and any instrument passed through the urethra can damage the lining and trigger the scarring process. Among procedure-related strictures, transurethral surgery (operations performed through the urethra, such as prostate procedures) is the single most common culprit.
In low- and middle-income countries, external trauma accounts for about 36% of cases, driven largely by road traffic injuries. Straddle injuries, pelvic fractures, and direct blows to the groin can all damage the urethra enough to produce a stricture months or years later.
A chronic skin condition called lichen sclerosus is a less common but particularly troublesome cause. It produces ongoing inflammation and scarring that tends to affect longer stretches of the urethra, especially in the penile portion. Lichen sclerosus also carries a small but real risk of progressing to squamous cell carcinoma in 2 to 8% of affected patients, which is one reason these strictures receive close monitoring.
Infections, including sexually transmitted infections that cause urethritis, can also lead to strictures, though this has become less common with modern antibiotic treatment. In many cases, no clear cause is ever identified.
What It Feels Like
The hallmark symptom is a weak or slow urinary stream. Because the channel is physically narrower, urine can’t flow at a normal rate. You may notice the stream splits or sprays, takes longer to start, or dribbles at the end. Some people feel like they can never fully empty their bladder and need to urinate again shortly after finishing.
Other common symptoms include straining to urinate, a sensation of incomplete emptying, and frequent urinary tract infections. In more severe cases, you might experience pain during urination or notice blood in the urine. A very tight stricture can make urination extremely difficult or, in rare situations, block flow almost entirely, which is a medical emergency.
How Strictures Are Diagnosed
Diagnosis typically starts with a flexible cystoscopy, where a thin camera is passed into the urethra. This confirms whether a stricture exists and gives a general sense of its severity. However, cystoscopy has a key limitation: once the camera reaches a narrowing it can’t pass through, there’s no way to see what’s beyond it. Pushing the scope further would actually stretch the stricture rather than examine it, turning a diagnostic test into a treatment.
For a more complete picture, doctors use a retrograde urethrogram (RUG), an X-ray taken while contrast dye is gently injected into the urethra. This maps the exact location, length, and severity of the narrowing, all of which are essential for planning the right treatment. When there’s concern about scarring closer to the bladder, a voiding cystourethrogram (VCUG) adds another view by imaging the urethra while the patient actively urinates, which opens up the deeper portions of the urinary tract that a standard RUG can miss.
What Happens Without Treatment
A stricture won’t resolve on its own. Scar tissue doesn’t remodel back into normal, flexible urethral lining. Left untreated, the narrowing tends to worsen over time, and the chronic obstruction puts increasing back-pressure on the bladder. The bladder muscle thickens as it works harder to push urine through the constriction, and eventually it can weaken. Residual urine sitting in the bladder raises the risk of recurrent infections and bladder stones. In prolonged, severe cases, the back-pressure can reach the kidneys and impair their function.
Treatment Options
Dilation and Internal Cutting
The simplest approach is urethral dilation, where progressively wider instruments are passed through the stricture to stretch it open. A related procedure, internal urethrotomy, uses a small blade or laser to cut through the scar tissue from the inside. Both are quick, minimally invasive, and can be done as outpatient procedures.
The catch is durability. About 50% of patients develop a recurrence within six months after internal urethrotomy. These procedures work best for very short, shallow strictures that haven’t been treated before. With each repeat procedure, the success rate drops and the scarring can actually worsen.
Urethroplasty
For longer strictures, recurrent strictures, or dense scarring, urethroplasty is the more definitive option. This is open surgery that either removes the scarred segment and reconnects the healthy ends, or patches the narrowed area with a graft, often taken from the inner lining of the cheek. Reported five-year success rates vary depending on how “success” is defined, ranging from about 75% using generous criteria down to around 23% when the strictest measures are applied. The wide range reflects differing definitions: some studies count any improvement in flow as a success, while others require a completely normal urethra on imaging.
Recovery involves wearing a urinary catheter for roughly three to four weeks after surgery. During that time, the repaired urethra heals around the catheter, which keeps the channel open. After the catheter is removed, most patients notice a significant improvement in their stream. Follow-up imaging and flow tests are standard in the months and years that follow, since recurrence is possible even after surgical repair.
Self-Catheterization to Prevent Recurrence
For patients who’ve had dilation or internal urethrotomy, periodic self-catheterization can help keep the urethra from scarring shut again. This involves passing a thin, lubricated catheter through the urethra on a regular schedule, typically for about six months after the procedure. In one study of patients with recurrent strictures, those who stuck with the self-catheterization program maintained improved urine flow throughout the observation period, and none required repeat surgery. The dropout rate was notable, though: about a third of patients stopped the regimen before the six months were up, which highlights that consistency is challenging but important.
Who Gets Urethral Strictures
Strictures are overwhelmingly a condition of men, because the male urethra is much longer and passes through the prostate and penis, creating more opportunities for injury and scarring. The prevalence in men ranges from roughly 229 to 627 per 100,000, with a sharp increase after age 55. In women, strictures are far less common but do occur, most often after traumatic or repeated catheterization.
Men who have had prostate cancer treatment, hypospadias repair in childhood, or any history of urethral instrumentation are at elevated risk. In younger men, pelvic trauma from accidents or sports injuries is a more typical trigger.