It's unusual to find blood in your semen when you ejaculate, but try not worry – it is usually only temporary and the cause is rarely anything sinister.
The semen may be bloodstained, brownish-red in colour or have a pink tinge – but in any case, you should see your doctor for a full investigation.
Before you read on, it's worth making sure that the blood you have found is definitely in your semen and not in your urine, which can indicate a different cause. Information on blood in the urine is covered elsewhere.
In many cases, no obvious cause can be found for blood in the semen, in which case it is most likely to be the result of a forgotten or unnoticed injury to the genitals, such as a trouser-zip accident.
The other likely causes of blood in the semen are outlined below. This is intended to give you a better idea of the underlying problem, but you should not use it to diagnose yourself with a condition – always see your doctor for a proper diagnosis.
If you have recently had prostate surgery or a procedure such as extracorporeal shockwave treatment, this will be the most obvious cause of the blood. The blood should soon pass within three to four weeks, but you should still get it checked by your doctor.
If you haven't had any surgery or procedure to your lower body, the cause is likely to be one of the following:
- Prostatitis (inflammation or infection of the prostate gland, where semen is made) – you may also have pain when urinating and ejaculating, blood in your urine and discomfort around your scrotum and tip of your penis, and you will probably need antibiotics.
- An infection of the testicle and sperm duct (known as epididymo-orchitis) or a urinary tract infection – you may also have pain when urinating and may need to urinate more frequently. This is treated with antibiotics.
- Injury to the testicles or perineum (the area of skin between the scrotum and bottom) – this may have happened as you were zipping up your trousers or after vigorous sex.
Less common causes
Less commonly, blood in the semen may be a result of:
- a blood clotting disorder
- stones forming in the prostate or the seminal vesicle (a gland above the prostate gland)
- prostate cancer, testicular cancer or bladder cancer
If you have any of these conditions, you will be under the care of a specialist.
If you aged under 40
If you are younger than 40 and you have one episode of blood in a month, it is unlikely that the cause is anything serious and you shouldn't need a hospital referral.
Your doctor may ask you to provide a sample of ejaculate, and may also request a urine sample and take a blood sample if they suspect there is an infection.
When you should be referred
Your doctor should refer you to a urologist (specialist who treats problems of the urinary system) for further assessment if you are aged 40 or over and:
- you have experienced more than one episode of blood in your semen
- you have experienced this for over a month
- you have another abnormality as well
You may have an ultrasound or biopsy of your prostate gland (where a sample of tissue is taken for analysis).
A serious underlying cause like prostate cancer is rare, but should be investigated in this case.