What Can Cause Worm-Like Blood Clots in Urine?

If blood is in your ureters or urethra long enough to start clotting, it’s possible it will come out in a worm-like shape. However, this is very rare.

Having blood in your urine, called hematuria, makes your pee turn dark or reddish. It’s not very common. Having worm-like blood clots in your urine is even less common.

In these cases, a large amount of blood may have been caught in your ureters or urethra long enough to start clotting. When it comes out of your bladder, the clotted blood sticks together and forms a long string that resembles the tube shape of your ureters and urethra.

There are many possible causes for these worm-like blood clots. Read on to learn about these causes, when it might be something other than a blood clot, and when to get medical help.

Blood clots in your urine aren’t always considered an emergency if you’re not feeling any pain or having trouble peeing.

In most cases, you can schedule an appointment with a doctor when you notice any blood clots in your urine. They can give you a physical exam, make a diagnosis, and prescribe the appropriate treatment.

Preventable medical errors kill about 22,000 patients a year, according to research from the Yale School of Medicine. That’s much less than a previously reported number of 250,000 deaths a year where medical error is to blame.

Medical emergency

Some causes of worm-like blood clots in your urine are more serious and may require immediate medical attention.

• severe pain when you pee
• difficulty peeing
• not being able to pee at all
• constant pain in your groin or lower back
• other tissues coming out in your urine

Worm-like blood clots in the urine most often occur from bleeding in the bladder or urethra, especially if you don’t feel any pain or discomfort. This is because the tube-like shape of the urethra squeezes blood clots into a worm-like shape as they exit the body.

Some of the most common causes of worm-like blood clots include:

• urinary tract infections (UTIs) that cause swelling in the urinary tract
• kidney stones in the ureters, which can irritate tissues
• groin injuries that can cause bleeding into the ureters, bladder, and urethra
• medications that affect your blood, such as aspirin or blood thinners

Some less common and more serious causes can include:

• kidney disease, which may cause swelling, bleeding, and infections in the kidneys
• cancer in the kidneys or bladder, which may irritate tissues or block urine from draining properly
• sickle cell anemia, which may cause red blood cells to get trapped in blood vessels and build up

Stringy blood clot in urine in females

Some conditions that can cause stringy or worm-like blood clots in the urine are specific to the female reproductive system, such as menstruation or endometriosis.

Endometriosis is a condition that can cause scar tissue to build up in your body and around your organs. When endometrial tissue develops around your urinary tract, it can irritate tissues or even grow through those tissues and inside them. This can cause bleeding that clots in your urinary tract.

Stringy blood clots in urine in males

Other conditions are specific to the male reproductive system. For example, blood from the prostate can also clot and build up in the urethra. This causes clots to take a worm-like shape before they’re expelled.

An enlarged prostate that’s pushing on the bladder and causing swelling or infection in the urinary tract may cause this.

Kidney worms, also called Dioctophyme renale, are a type of parasite. They sometimes appear in urine but are very rare. People can contract an infection by eating raw or undercooked fish or frogs containing the worms’ larvae.

Seeking medical help after seeing worm-like clots in your urine can help you get a diagnosis and treatment in the rare cases you do have a parasite.

Occasionally having blood in your urine isn’t always a cause for concern. But consider contacting a doctor if you start to notice pain or discomfort when you urinate or pain in your pelvis or lower back.

Some other symptoms to get medical attention for include:

• fatigue
• abdominal pain
• losing your appetite
• losing weight for no obvious reason
• deep bone pain
• swelling in your legs
• fever

Here are answers to some common questions you may have about worm-like blood clots in the urine.

What does a blood clot in urine look like?

Blood clots don’t always look worm-like in your pee. Most of the time, they look like small, reddish, or darkish chunks floating in otherwise normally colored urine.

This is especially common if the clots are from menstruation or a minor injury to the pelvic area. Sometimes, you’ll see just one small chunk by itself.

But you may also have several chunks of different sizes come out when you urinate or appear every time you urinate for a certain period of time.

What if I have stringy blood clots in my urine but no pain?

Stringy blood clots in your urine aren’t necessarily a cause for concern if you’re not experiencing any pain or any other concerning symptoms, such as changes in your peeing habits.

But these blood clots can sometimes indicate the growth of masses or tumors near the urinary tract, which can sometimes be cancerous.

Are blood clots in the bladder dangerous?

Blood clots in the bladder aren’t always dangerous. But blood clots can also be a symptom of serious injuries or conditions, like prostate cancer or endometriosis, that need treatment to prevent complications.

These blood clots may appear in the pee regularly or show up alongside discolored urine and constant pain.

Worm-like blood clots in the urine aren’t always an issue if you’re not experiencing any pain or other symptoms.

But consider getting medical help if you’re concerned, or if you’re experiencing significant pain or noticeable changes in your peeing habits.

Last medically reviewed on April 5, 2023