Varicoceles are similar to varicose veins, but they occur around the testicles rather than the legs. They do not usually cause any serious problems, but they can impact male fertility.

They happen when certain veins in the scrotum become enlarged, due to a malfunction in some of the valves involved in pumping the blood. They affect around 15 percent of males, and they tend to form between the ages of 15 and 25 years.

Varicoceles normally affect just one side, usually the left.

This article will look at the causes, symptoms and treatments of varicoceles.

  • Varicoceles are similar to varicose veins but they affect the testicular area in men.
  • They are thought to affect 15 percent of men, usually between the age of 15 and 25 years.
  • The exact cause is unknown, but it may be similar to that of varicose veins.
  • They are not usually painful.
  • Varicoceles are not usually serious, but complications include fertility problems.
  • Surgery is possible, if complications arise.
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Varicoceles refer to enlarged veins in the testes.

A varicocele is an enlargement of the veins in the scrotum, the the bag that contains the testes. They are similar to varicose veins of the leg.

They affect a type of vein known as the pampiniform plexus.

The pampiniform plexus is found in the spermatic cord. This cord also holds the vas deferens, the tube that carries sperm, and the testicular artery, which transports blood to the testicles.

The creation of sperm is most efficient at around 34.5 degrees Celsius, or 94.1 degrees Fahrenheit, rather than the body’s standard 37 degrees Celsius. This is one reason why the testes are physically separate from the trunk of the body.

The main role of the pampiniform plexus is to cool the arterial blood before it reaches the sperm. It does this through a “heat exchange” mechanism.

Varicoceles can disrupt this cooling system. This can prevent the testicles from producing good quality sperm.

Treatment is not usually necessary, unless there is:

  • pain and discomfort
  • a low sperm count
  • infertility that has continued for at least 2 years and is otherwise unexplained

In these cases, surgery may be recommended.

Three surgical options are possible:

Varicocelectomy: Open surgery is performed under local or general anesthetic. The surgeon will access the area through the groin, or less commonly, through the abdomen or upper thigh. Using ultrasound and surgical microscopes, they will close the affected veins to reroute the blood through other, healthier vessels. Post-surgical pain is normally minimal, and the individual can soon return to normal activities.

Laparoscopic surgery: The surgeon makes a small incision in the abdomen and passes a tiny surgical instrument through the opening.

Percutaneous embolization: A radiologist inserts a tube, or catheter, into the body through the neck or groin. Instruments are passed through the tube, and the surgeon uses coils or chemicals to block the vein by scarring it. This is a minimally invasive intervention. It can be done as an outpatient procedure, and recovery time is relatively short.

Risks of surgery

These procedures are relatively safe but, as with any surgery, there are some risks.

These include:

  • artery damage
  • further testicular atrophy
  • infection
  • bruising, swelling, or a buildup of fluids in the area
  • abdominal pain

Rarely, a renal vein thrombosis may develop. This can affect the kidney and may need further surgery.

Sometimes, the veins through which the blood passes after surgery also enlarge. Further treatment may then be necessary.

Varicoceles rarely cause pain, but if they do, the pain will probably:

  • be worse when standing or during physical exertion
  • vary from sharp to dull pain
  • decrease when lying on your back
  • worsen as the day goes on

Varicoceles will often go unnoticed, but a physician may notice them during a medical examination.

However, the individual should see a doctor if they notice:

  • any change in the size, shape, or appearance of the testes
  • a lump
  • fertility problems
  • swelling in the scrotum
  • veins that show as unusually large or twisted

In some cases, a varicocele can lead to complications.


Infertility is the most serious complication that can occur. It probably happens because the increased amount of blood in the region raises the temperature of the testicles.

Between 35 and 44 percent of men with primary infertility have varicoceles. Primary infertility is when a couple have not successfully conceived after 12 months of trying.

Varicoceles affect 45 to 81 percent of men with secondary infertility. This is when a couple has been able to conceive at least once but are no longer able to.

Research published in 2016 found that, out of 7,035 healthy young men who were surveyed from 1996 to 2010, 15.7 percent had varicoceles. Those with varicoceles also had poorer semen quality.

Sperm production is most efficient at a temperature slightly lower than body temperature.

Testicle shrinkage

A varicocele can lead to testicular atrophy, or shrinkage. Sperm-producing tubules make up the bulk of the testicle. If they are damaged, the testicle might become smaller and softer.

Hormone imbalances

As the cells react to the increase in pressure, a change in hormones can result. There may be higher levels of luteinizing hormone (LH). This hormone is present in both men and women, but it is higher in women. There may also be normal-to-subnormal levels of testosterone.

One explanation for varicoceles is that the valves in the spermatic cords, which carry blood to and from the testicles, stop working correctly.

Why this happens is not entirely clear, but it is similar to what happens when varicose veins occur in the leg.

One-way valves in the veins should always allow blood to flow toward the heart. Faulty valves can disrupt the blood flow. The blood pools rather than moving smoothly on. This build-up of blood causes the vessels to dilate.

As with any other organ, a disruption in blood flow can eventually stop it from working properly.

Varicoceles can be classified as:

Pressure type: The spermatic vein fills up with blood, giving rise to a grade I varicocele.

Shunt type: A severe buildup causes damage to the spermatic vein and other veins, leading to a larger, grade II or III varicocele.

The left testicle is most likely to be affected. However, even if only one side contains a varicocele, this can impact sperm production on both sides.

Risk factors

There are no particular risk factors known for varicoceles, but they are most likely to appear during puberty. Being overweight may reduce the risk, while being taller appears to increase it.

It was previously thought that once a man has fathered a child, he is unlikely to be infertile after this, but in 1993, researchers concluded that this was probably untrue. Instead, they suggest that the risk of infertility may increase over time.

If varicoceles develop in a man aged over 40 years, it is more likely to be due to a blockage in a larger vein in the abdominal area, possibly as a result of a kidney tumor.

If a varicocele is not serious enough for surgery, wearing supportive underwear may help reduce any pain.

Various alternative therapies are on sale for treating low sperm count, but it is best to speak to a doctor first.

There are three grades of varicocele:

  • Grade 1: The smallest type, this is not visible, but a physician can feel it if they use a Valsalva maneuver.
  • Grade 2: This is not visible, but it can be felt without a Valsalva maneuver.
  • Grade 3: The varicocele is visible.

If the growth is large enough, it may feel something like a soft “bag of worms.

A subclinical varicocele is a varicocele that can only be detected through imaging tests. This could be scrotal thermography or a Doppler reflux test, a type of ultrasound.

An ultrasound test will also help to rule out other possible causes of the varicocele, such as a tumor on or near the spermatic vein.

Other possible tests include a semen analysis and hormone tests to detect high follicle-stimulating hormone (FSH) and low testosterone. These may be done if the doctor suspects a testicular dysfunction.

A varicocele does not usually pose a risk, but if there is any change in shape, size, or consistency in the genital region, it is important to see a doctor.