Membranous Urethra

What is the membranous urethra?

The membranous urethra is the middle section of the urethra in people designated male at birth (DMAB). The urethra is a tube that empties urine from the bladder. In people DMAB, the urethra also carries semen.

In both sexes, the urethra starts at the bottom of the bladder. In people DMAB, it ends at the tip of their penis. In people designated female at birth (DFAB), it ends at the urethral opening, just beneath their clitoris. In people DFAB, the urethra is much shorter than in those DMAB, and doesn’t have a membranous section.

What is the purpose of the membranous urethra?

The membranous urethra is the narrowest and tightest part of the urethra, so it helps you hold urine in. It’s surrounded by a circular muscle called a sphincter. The muscles tighten when you need to hold urine and relax when you’re ready to urinate (pee).

How long is the male urethra?

The entire urethra is about 8 inches long in people designated male at birth, but the membranous urethra (the shortest section) is only about 1/2 an inch long.

Where is the membranous urethra located?

The membranous urethra is part of the male reproductive system. It starts just below their prostate, which is a gland that helps make semen. It passes through their pelvic floor and ends above the base of their penis. At this point, their membranous urethra becomes their penile, or spongy, urethra and extends down through the length of their penis.

What does the membranous urethra look like?

The entire urethra looks a bit like an “S” turned on its side. The membranous urethra is the first, short curve of the “S.”

What is the membranous urethra made of?

Thick, elastic muscle fibers make up the outermost layer of the membranous urethra. They help this section of your urethra contract and stay tight. The middle layer contains submucosal tissue containing blood vessels, lymph vessels and some glands. The inner layer of the membranous urethra is epithelial tissue, which protects your urethra from urine, semen and toxins.

What conditions and disorders affect the membranous urethra?

Some of the most common conditions that affect your urethra, including the membranous urethra, are:

• Urethral cancer: Urethral cancer usually starts in the cells of your urethra’s inner lining. It’s a rare form of cancer that is more common in males than females.
• Urethral strictures: Urethral strictures are blockages or narrowing in your urethra, usually due to an injury, surgery, infection or swelling. Providers call strictures in the membranous urethra posterior strictures. Strictures are more common in males.
• Nongonococcal urethritis: Urethritis is inflammation of your urethra. It can be the result of a viral or bacterial infection but is usually due to sexually transmitted infections (STIs). It tends to be more common in males.
• Urinary tract infections (UTIs): A UTI is an infection in any part of your urinary system, which may include your kidneys, bladder, ureters or urethra. UTIs tend to be more common in females.

What are the symptoms of urethral disorders?

You may not have any symptoms if you have a urethral disorder. But if you notice any of the following, talk to your healthcare provider:

• Abdominal pain.
• Bloody urine (hematuria) or semen (hematospermia).
• Burning sensation when you urinate.
• Difficulty urinating.
• Discolored or cloudy discharge from your urethra.
• Dysuria (painful urination).
• Sore or swollen penis.
• Urinary incontinence (uncontrollable urine leakage).

How can I take care of my membranous urethra?

You can take care of your urethra by following these tips for a healthy urinary tract:

• Avoid excessive amounts of alcohol and caffeine.
• Do Kegel exercises (pelvic floor exercises).
• Don’t smoke or use tobacco products.
• Drink plenty of water to stay hydrated.
• Eat fiber-rich foods to avoid constipation.
• Fully empty your bladder each time you urinate.
• Practice safe sex by using condoms.
• Stay active and maintain a bodyweight that’s healthy for you.
• Urinate after sex.
• Urinate as often as you need to.
• Wear cotton underwear and loose-fitting pants.

What questions should I ask my doctor about urinary tract problems?

If you have a problem with your urethra or any urinary tract condition, you may want to ask your doctor these questions:

• Are there steps I can take to prevent urinary tract conditions?
• Are urinary tract problems related to aging?
• What’s causing my urinary tract condition?
• Will I develop incontinence?

A note from Cleveland Clinic

The membranous urethra is the middle section of the urethra in people designated male at birth. It carries urine and semen out of your body. Muscles around this part of the urethra help you hold in your urine. Infections, injuries, swelling and other conditions can affect the membranous urethra. Talk to your doctor right away if you have any problems with urination, such as pain or urine blockages.