Blood in Semen

ByGeetha Maddukuri, MD, Saint Louis University
Reviewed/Revised Dec 2022

Blood in semen (called hematospermia, because sperm are mixed with blood in the semen) can be a frightening symptom, but it is usually not a sign of a serious problem. Blood in semen is not usually a sign of cancer and does not affect sexual function.

Semen is composed of sperm from the epididymis and fluids from the seminal vesicles, prostate, and small mucous glands that provide fluids to nourish sperm. Thus, blood could come from injury to any of these structures. (See also Overview of Urinary Tract Symptoms.)

Causes of Blood in Semen

Most cases of blood in semen are

  • Idiopathic, that is they arise without warning and doctors cannot find a cause

Such cases resolve on their own within a few days to a few months.

The most common known cause is

Bleeding can last a few weeks or so after a prostate biopsy. Bleeding can also occur during the first week or two after a vasectomy.

Less common causes include benign prostatic hyperplasia (a benign enlargement of the prostate gland), infections (for example, prostatitis, urethritis, or epididymitis), and prostate cancer (in men over 35 to 40 years). Occasionally, blood in semen occurs in men who have tumors of the seminal vesicles and testes. A mass of abnormal blood vessels (hemangioma) in the urethra or the ducts that connect the testes to the urethra (spermatic ducts) may cause quite a bit of blood to appear in semen.

Schistosoma haematobium, a parasitic worm that commonly causes infections (schistosomiasis) in Africa, India, and parts of the Middle East can invade the urinary tract, causing blood to appear in the urine and often in semen. Schistosomiasis is unlikely in men who have not spent time in these areas. Tuberculosis may cause blood in semen.

Evaluation of Blood in Semen

Although blood in semen can be alarming, it is not usually serious, and it does not require an immediate evaluation. The following information can help men decide when a doctor's evaluation is needed and help them know what to expect during the evaluation.

Warning signs

Certain symptoms and characteristics are cause for concern. They include

  • Bleeding lasting longer than 1 month (unless there was a recent prostate gland biopsy)

  • A lump that can be felt in the scrotum

  • Travel to a region where schistosomiasis is prevalent

When to see a doctor

Men who have warning signs should see a doctor. Timing is not critical, and a delay of a week or so is not harmful. Men who do not have warning signs and are younger than age 35 do not need to see a doctor unless they have other symptoms, such as pain in the scrotum or groin or pain during urination. Men who do not have warning signs and are over 35 should see a doctor within a few weeks.

What the doctor does

Doctors first ask questions about the man's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of the blood and the tests that may need to be done.

Doctors ask

  • When the man first noticed the blood

  • Whether he has recently had a urinary tract procedure, such as a biopsy of the prostate gland, injury

  • Whether he has any symptoms that might suggest a urinary tract infection (for example, blood in the urine, difficulty starting or stopping urine flow, burning during urination, or a discharge from the penis)

  • Whether he has a tendency to bleed excessively or a disorder that causes bleeding

  • Whether he is taking antiplatelet drugs or blood thinners

  • Whether he has a prostate disorder (for example, benign prostatic hyperplasia or radiation treatment for prostate cancer)

Doctors examine the genitals for redness, a lump, or tenderness. A digital rectal examination is done to examine the prostate for enlargement, tenderness, or a lump.

Doctors can often determine what causes are likely after taking a history and doing an examination. For example, the following kinds of information can provide clues. In men with an abnormal prostate detected during a digital rectal examination, a prostate disorder is likely, such as prostate cancer, benign prostatic hyperplasia, or prostatitis. In men with urethral discharge, urethritis is likely. In men with tenderness of the epididymis, epididymitis is likely. However, such abnormalities may not be the cause of blood in semen. For example, most older men have benign prostatic hyperplasia, yet few of them have blood in semen.

In men who have bleeding that has lasted less than a month, have not been in areas where schistosomiasis is prevalent, and have no warning signs or abnormalities on examination, a cause cannot usually be found.


In most cases, especially in men younger than 35 to 40 years and in men who recently had a prostate biopsy, blood in semen is not serious and resolves on its own. Urinalysis and urine culture are usually done. Further testing is not usually needed unless there are urinary symptoms that suggest an infection or other disorder. However, if the doctor suspects certain potentially serious disorders, further testing is done, for example, some doctors typically do tests for prostate cancer on men over 40.

Testing includes prostate-specific antigen (PSA) testing and transrectal ultrasonography (TRUS). Occasionally, magnetic resonance imaging (MRI) and cystoscopy (which involves inserting a thin, flexible viewing tube through the urethra to enable doctors to see inside the urethra and bladder) are needed. Semen inspection and analysis are rarely done.

Treatment of Blood in Semen

Treatment is directed at the cause if known. Often no treatment is needed, and the blood goes away on its own. Sometimes, as is the case after a prostate biopsy, the blood in semen may persist for several months.

Key Points

  • In most cases, a cause cannot be found or bleeding occurs after a prostate biopsy.

  • Blood in semen is not usually a sign of cancer and does not affect sexual function.

  • More detailed evaluation is needed mainly for men with symptoms that last longer than a month, who are over 40, or who have abnormal findings.

  • Doctors may need to test for schistosomiasis in men who have traveled to Africa, India, or certain parts of the Middle East.

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