Definition of blood in semen
Blood in semen (hematospermia) can be frightening, but the vast majority of time, it’s not cause for serious concern. Blood in semen is uncommon, and, most often, it goes away on its own.
Causes of blood in semen
Semen consists of sperm and fluids released by the prostate and other glands. The fluids (also called ejaculate) join the sperm as they pass through a series of tubes to the urethra for ejaculation. A number of things can break blood vessels along this route or along the urinary route to the urethra. Broken vessels then leak blood into the semen, urine or both.
Often, no cause can be found for blood in semen. For men under age 40, infection is the most common cause. Infection is usually accompanied by other signs and symptoms, such as fever, genital or urinary pain, difficulty urinating, or blood in your urine.
For men age 40 and older, blood in semen is a slight predictor of a cancer (malignancy), most often prostate cancer. So a more careful evaluation is merited when this sign appears in this age group. But the risk is low. In follow-up studies of more than 800 men who had blood in their semen, cancer was found in less than 4 percent (on average).
More common causes of blood in semen:
- Genital herpes
- Interrupted sex
- Prolonged sexual abstinence
- Prostate biopsy
- Prostate gland enlargement
- Testicular trauma
- Vigorous sex
Less common causes
- Benign growths (cysts, polyps) in the bladder, urethra or prostate
- Bladder cancer
- Fragile blood vessels
- Prostate cancer
- Testicular cancer
- Von Willebrand disease
- Warfarin side effects
When to see a doctor
If you’re under age 40 and see blood in semen, you probably don’t need to see the doctor as long as:
- You have no other symptoms
- You’ve had a recent prostate exam or vasectomy, which could explain short-term bleeding
- There isn’t a lot of blood in the semen and it happens infrequently, then goes away
Make an appointment with your doctor if:
- You’re 40 or older
- Blood in semen persists longer than three to four weeks
- You have other signs and symptoms, such as genital or urinary pain, pain during ejaculation, fever, difficulty urinating, or blood in your urine
- You have other risk factors, such as a history of cancer, bleeding disorders, trauma, or genital or urinary system malformation, or you’ve recently engaged in behaviors that put you at risk of sexually transmitted infections