Many men have enlarged veins in the scrotum, which is the pouch that holds the testicles. Doctors call these veins varicoceles. Many men with varicoceles have no symptoms, but some may have fertility issues.

Varicoceles are common, affecting 10 to 15 percent of men. Doctors continue to debate the role of varicoceles in infertility.

Some research suggests that treating a varicocele may improve fertility outcomes. However, a systematic review states that the available evidence is weak and that doctors must conduct more research.

In this article, learn more about whether a varicocele affects fertility, as well as when to see a doctor.

Diagram of a varicoceleShare on Pinterest
Varicoceles affect about 10 to 15 percent of men.
Image credit: BruceBlaus, 2015

A varicocele occurs when a bulge results from enlarged veins inside the scrotum. The swelling typically resembles an enlargement above the testicle, without discoloration.

The pampiniform plexus is a group of veins inside the scrotum. These veins help cool the blood before it travels to the testicular artery, which supplies the testicles with blood.

If the testicles are too hot, they cannot make healthy sperm. Sperm health affects fertility, so it is essential that the veins can cool down the blood.

Most people with a varicocele do not have symptoms, but some may experience fertility issues.

When someone has a varicocele, they may also experience swelling and tenderness of the scrotum.

Most men who have varicoceles do not have fertility problems. Infertility rates among those with varicoceles, however, are higher than those without them. This difference may be because varicoceles interfere with the body’s ability to make and store sperm.

A 2014 study gathered data on 816 men with infertility issues, and almost one third had a varicocele. This frequency suggests that varicoceles are sometimes, but not always, a factor in infertility.

Research on whether treating varicoceles can improve fertility is mixed.

A 2012 meta-analysis of previous studies found some evidence that treating a varicocele might improve fertility, especially if the cause of a couple’s infertility is unknown. However, the researchers caution that the evidence is weak, and so more research is needed.

The main concern with varicoceles is that the bulge of veins may damage sperm and lower sperm count. In those individuals with an average sperm count, a varicocele is unlikely to cause infertility.

When a couple cannot conceive, it is vital to do a variety of tests, including a sperm count, and not assume that a varicocele is necessarily the sole cause.

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A doctor may use an ultrasound to diagnose a varicocele.

A varicocele occurs when veins in the scrotum become enlarged.

Every vein has a valve that prevents blood from flowing backward, but sometimes the valve fails. This causes blood to flow back, damaging the vein and causing swelling.

Doctors do not fully understand what causes the valves to fail and cause varicoceles. They are common and do not usually mean that a person has an underlying health problem.

Research published in 2014 found that smoking may be a risk factor for varicoceles, as it damages a person’s blood vessels. The same study found no link between alcohol or occupation and varicoceles.

Rarely, a growth in the stomach can put pressure on the veins, causing a varicocele. This issue is more common in men of more than 45 years of age.

In many people, a varicocele has no apparent cause.

Most men who have varicoceles do not notice anything unusual, although some people report a heavy sensation or occasional throbbing in the scrotum. Many of those affected only discover they have a varicocele after experiencing infertility issues.

A doctor can often diagnose a varicocele during a physical exam by looking at the scrotum and feeling for lumps and unusual blood vessels.

If a doctor suspects a varicocele, they may order an ultrasound, which is a painless imaging test that allows the doctor to see the veins inside the scrotum.

If the person is having problems with fertility, the doctor may also order a semen analysis to check sperm quality.

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If a man has varicoceles and a low sperm count, he may need treatment.

Varicoceles that do not cause symptoms do not require treatment. A varicocele may need treatment when:

  • A man has a varicocele and a low sperm count or other problems with sperm.
  • The varicocele is causing pain or swelling.
  • A couple has unexplained infertility, and the male has a varicocele.

When people chose to have treatment, they have two different options:


Embolization is surgery that temporarily cuts off the blood supply. A doctor can carry out this procedure in their office with local anesthesia, meaning a person will not feel any pain in the area.

During embolization, a doctor inserts a needle into a vein usually through the groin. Sometimes, they may insert a needle through the neck. The needle helps the doctor access the veins in the scrotum and block off the varicocele.

A person may experience some pain and tenderness after the procedure, but recovery time is short, and the individual can immediately return to their usual activities.

A 2012 study suggests that embolization may be unsuccessful in as many as 19.3 percent of cases. If embolization does not work, surgeons may need to try a different procedure to treat the varicocele.


A doctor can surgically remove a varicocele by blocking the blood flow to the damaged vein. This surgery is called a varicocelectomy.

A person will receive a general anesthetic before the varicocelectomy, so they will be asleep and unable to feel any pain during the procedure. A person may experience some pain and tenderness for several days afterward.

Surgery is more effective than embolization with a failure rate of less than 5 percent.

Laparoscopic surgery uses a smaller incision than open surgery and requires less recovery time but also requires a very skilled surgeon. Open surgery uses a larger cut into the scrotum.

The outlook for men who choose to treat a varicocele is relatively good. A 2014 study of men with low sperm count and a varicocele found that surgery increased their sperm count, on average, from 2.4 to 11.6 million per milliliter.

However, in the same study, fertility rates remained relatively low. Out of 102 participants, 17 couples conceived naturally. This suggests that treatment may increase fertility, but will not cure infertility in all men.

Men who have a varicocele and a history of infertility should discuss with their doctors the risks and benefits of treatment. In some cases, surgery may be the safest option for increasing fertility. In other situations, a couple may have better results with assisted fertilization techniques, such as intrauterine insemination (IUI) and in vitro fertilization (IVF).

There is no evidence that varicoceles inevitably make a man infertile. In 10 to 20 percent of men, the varicocele comes back after surgery.

Men who notice swollen veins should not assume they will have fertility issues, though they may wish to discuss the risk with a doctor.