A varicocele is a varicose vein above the testicles. All veins have valves inside them that keep the blood moving in one direction. With varicose veins, these valves have failed and blood can pool, eventually making the veins bulge.

Blood in the body is cooled as it moves through the veins back to the heart. If it sits in one place, the temperature of the blood increases. Therefore, in the testes, if the temperature of the blood increases because of varicoceles, male fertility can be reduced.

Sperm are sensitive to heat, and high temperatures can interfere with the production of sperm. Not all men with varicoceles are infertile. Approximately 10-15% of men develop a varicocele during their lifetime.

Learn more about Varicoceles

Varicoceles symptoms

Varicoceles usually appear in the left testicle. Varicoceles are often painless. Symptoms include:

  • Dilated veins above the testis that feel like 'a bag of worms'.
  • A dull, constant ache or sensation of heaviness in the testicle.
  • Aches more noticeable after long periods of standing.
  • Sometimes the decrease in circulation to a testicle will make it shrink in size.

Any persistent pain in the genital area is not normal. Visit your GP or consultant if you notice any of the above symptoms.

Varicoceles diagnosis

Varicoceles can be large or small. Prominent ones can be seen with the naked eye. Your doctor will also feel your testicles for any evidence of swollen veins.

If infertility is suspected, the doctor may also examine a sample of your semen.

Varicoceles treatment

Usually, no treatment is required, although if you're uncomfortable you may be advised to wear supportive underwear. 

However, if you're in great discomfort or the doctor suspects a potential fertility problem, you may be offered surgery to tie off the leaking veins. One method is embolisation: small tungsten coils are inserted to block the veins leading from the varicocele.

Need more information?

Speak to your GP or consultant if you notice any symptoms or to discuss varicoceles treatment options.


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