About varicocele

A varicocele is a group of enlarged veins next to your testicles. Your veins normally take blood away from the testicles. A varicocele develops when blood collects in the vein instead of flowing properly. This causes it to swell. A varicocele is similar to the varicose veins you can get in your legs.

Nine out of 10 varicoceles develop in the left testicle, although you can develop a varicocele in both testicles at the same time.

Around one in five men has a varicocele. They usually develop after puberty.

Symptoms of varicocele

You may not have any symptoms and your testicles may not look any different to normal.

However some men do have symptoms. These can include:

  • your left testicle looking swollen or hanging down lower than your right testicle
  • a heavy or dragging sensation in your scrotum
  • a dull pain in your groin or scrotum
  • your testicle looking swollen when you’re standing up, but not when you lie down

These symptoms may be caused by problems other than a varicocele. If you have any of these symptoms, see your GP for advice.

Complications of varicocele

A varicocele can affect your sperm and this makes it more difficult for you to have children. The reasons why this happens aren’t fully understood. However, doctor’s think that the pooled blood in your veins around your testicles may make your scrotum warmer, and this affects the quality of your sperm.

Causes of varicocele

The exact reasons why some men develop varicoceles aren't fully understood. One possible reason is that the valves in your veins don’t work properly. This means that they don’t close fully, which allows the blood in your veins to flow backwards. Your blood pools and this causes the vein to grow larger.

There may also be a genetic cause for varicocele. You’re more likely to develop a varicocele if a close relative has one, for example, your brother or father.

Rarely, varicocele can be caused by a tumour in your left kidney.

Diagnosis of varicocele

Your GP will ask about your symptoms and examine you. He or she may also ask you about your medical history.

Your GP will examine your scrotum and he or she may refer you to a urologist (a doctor who specialises in identifying and treating conditions that affect the urinary system).

At the hospital, you may have an ultrasound of your scrotum. An ultrasound uses sound waves to produce an image of the inside of your scrotum.

If you’re having difficulty having children, your GP may also ask you to have other tests. These may include blood tests to check your hormone levels and a sample of your semen.

Treatment of varicocele

If you don’t have symptoms from your varicocele and it isn’t causing you any problems, you may not need any treatment.


You can wear supportive underwear, which will help to ease any discomfort. If you need pain relief, you can take over-the-counter painkillers, such as paracetamol or ibuprofen. Always read the patient information that comes with your medicine and if you have any questions, ask your pharmacist for advice. If your pain is severe, talk to your GP.


If your varicocele is causing you discomfort or if it’s affecting your ability to have children, your doctor may suggest an operation to treat it. If your fertility is affected by your varicocele, then surgery to treat it may improve the quality of your sperm.

Varicocele embolisation is a procedure to block your veins where the blood is collecting in order to make them disappear. This is done by passing a thin tube into your vein. Special liquid is injected into your vein or small metal coils are inserted, which cause a blockage. Varicocele embolisation is usually done under local anaesthesia. This completely blocks pain from your scrotum and you will stay awake during the procedure.

Your doctor may suggest an operation to cut and tie the veins. This is called a called a varicocelectomy and it treats your varicocele while still keeping a healthy supply of blood to your testicles. The operation is carried out under general anaesthesia. This means you will be asleep during the operation.

A varicocelectomy can either be done as open surgery or as keyhole surgery. During open surgery, your surgeon will make a single cut either in your groin, just above your penis, or into your scrotum. During keyhole surgery, your surgeon will make two small cuts in your groin or into your scrotum. A tube-like telescopic camera will be used to allow your surgeon to see the varicocele and he or she will use specially designed surgical instruments to cut the vein.

Your doctor will discuss the different types of surgery with you to help you choose the best option for you.

Prevention of varicocele

You can’t prevent a varicocele from developing, but it's important to be testicle aware. Being testicle aware means checking your testicles every month, knowing what they look and feel like, and knowing what changes to look for.

Contact your GP if you notice any change in the shape or size of your scrotum or testicles.

Will surgery to treat a varicocele affect my ability to have sex?


No, surgery to treat a varicocele shouldn’t affect your ability to have sex.


A varicocele is treated by blocking the affected veins around your testicles or by cutting and tying them. This is done through a small cut either in your groin, just above your penis, or into your scrotum.

There is no evidence to suggest the operation will affect your ability to have sex. However, a potential complication of surgery is damage to the large blood vessel (artery) that supplies your testicle. This can affect the blood supply to your testicle, which may affect your fertility. However, this complication is uncommon, affecting less than one in every 100 men who have the operation.

If you have any concerns about the operation, please ask your surgeon for advice.

Will surgery to treat a varicocele improve my fertility?


An operation to treat your varicocele can improve your fertility. Around half of all men who have surgery to treat a varicocele improve their chances of conceiving a child with their partner.


A varicocele can affect the quality of your sperm and this affects your fertility making it more difficult for you to have children. Some men discover that they have a varicocele during tests to find out why their partner isn’t getting pregnant. Doctors think that a varicocele may make your scrotum warmer and that this increase in temperature may affect the quality of the sperm you produce.

After surgery to treat a varicocele seven in every 10 men find that the quality of their semen improves. Half of men who have the operation have better chances of conception. Because it takes about 72 days for your sperm to develop, you won’t see an improvement in your sperm count for about three to four months after your operation.

If you’re worried about your fertility or think it may be affected by a varicocele, see your GP.

What happens during varicocele embolisation treatment?


Embolisation is a technique to block the veins around your testicles. This stops blood flowing through them and reduces swelling and discomfort. It's usually done under local anaesthesia.


Varicocele embolisation is a procedure to block the enlarged veins causing your varicocele, making them disappear.

Varicocele embolisation is usually done by a radiologist – a doctor who specialises in using imaging techniques to diagnose and treat medical conditions. The procedure takes about 30 minutes and is usually done under local anaesthesia. This completely blocks pain from your scrotum and you will stay awake during the procedure. You may also be given a sedative and painkillers during the procedure to make you comfortable.

The radiologist will insert a fine plastic tube (catheter) through a large vein in your groin into the affected veins in your scrotum. He or she will take X-rays during the procedure to make sure the catheter is in the right place. Your radiologist will inject a special fluid or pass small metal coils down the catheter into the affected veins. This blocks the veins. When the radiologist is sure that the treatment has worked, he or she will remove the catheter. One of the doctors or nurses will press down firmly for a few minutes on the cut where the catheter went in. This should stop any bleeding.

You may need to stay in hospital overnight. Alternatively, you may be able to have the procedure as a day case and go home the same day.

As with every procedure, there are some risks associated with surgery for a varicocele. These include bleeding, bruising, infection and damage to the vein, although this is uncommon. We have not included the chance of these happening as they are specific to you and differ for every person. Ask your surgeon to explain how these risks apply to you.