The scrotum is a sac of skin that hangs from the body at the front of the pelvis, between the legs. It sits next to the upper thighs, just below the penis. The scrotum contains the testicles. These are two oval-shaped glands responsible for producing and storing sperm. They also produce several hormones, the main one being testosterone.

The scrotum hangs outside the body because it needs to maintain a slightly lower temperature than the rest of the body. This lower temperature helps to maintain sperm production. Scrotal tissues help protect the structures inside the testicles, where sperm and important hormones are produced.

In addition, the scrotum protects the testicles and major blood vessels, as well as tubes that release sperm from the testicles into the penis for ejaculation.

The scrotum is a sack of skin divided in two parts by the perineal raphe, which looks like a line down the middle of the scrotum.

The raphe joins the internal septum with the scrotum. The septum splits the scrotal sac into two parts with similar anatomy.

Each side of the scrotum usually consists of a:

  • Testicle. Each testicle produces hormones, the main one being testosterone, with the help of parts of the brain like the hypothalamus and pituitary gland. They also contain tubules and cells that produce sperm, or spermatozoa. Sperm are transferred from the testicle to the epididymis.
  • Epididymis. An epididymis is located on the top of each testicle. Each epididymis is a tightly coiled tube. They store sperm created in each testicle until they’re mature, usually for about 60 to 80 days. The epididymis also absorbs extra fluid secreted by the testicle to help move sperm through the reproductive tract.
  • Spermatic cord. Each spermatic cord contains blood vessels, nerves, lymph vessels, and a tube called the vas deferens. This tube moves sperm out of the epididymis into ejaculatory ducts. The blood vessels maintain the blood supply for the testicle, vas deferens, and cremaster muscle. The nerves transport information from the spinal cord to and from the scrotum, testicles, and cremaster muscle.
  • Cremaster muscle. Each cremaster muscle surrounds one of the testicles and its spermatic cord. The muscle helps to move the testicle toward and away from the body to maintain the ideal temperature for sperm production. This is why the scrotum hangs lower in warm conditions and closer to the body in cold weather.

All of these structures are surrounded by the scrotal wall. This wall is lined with smooth muscle called the dartos fascia muscle. This muscle, along with the cremaster muscles, help to expand or tighten the skin of the scrotum as it moves up and down.

Explore the interactive 3-D diagram below to learn more about the scrotum.

Many conditions can affect your scrotum and its contents. Here’s a list of some of the most common ones.

Inguinal hernia

An inguinal hernia happens when part of your small intestine pokes through an opening in your abdominal wall into your scrotum. Some inguinal hernias follow the path of the spermatic cord into the scrotum, while others stay outside it.

Symptoms of an inguinal hernia can include:

  • bulging or swelling around your pubic area that feels like it’s aching or burning
  • uncomfortable groin sensation or pain when you cough, laugh, or bend over
  • heaviness around your groin area
  • an enlarged scrotum

Some inguinal hernias can be dangerous if left untreated. You may need surgery to repair an inguinal hernia and prevent tissue death due to lack of blood flow.

Hydrocele

A hydrocele happens when excess fluid builds up in the cavities around one of your testicles. This is sometimes present at birth, but it can also result from an injury or inflammation.

Hydrocele symptoms include:

  • scrotal swelling that gets more noticeable as the day goes on
  • dull ache in your scrotum
  • feeling of heaviness in your scrotum

Hydroceles usually don’t require treatment unless they’re very large or painful. Most go away on their own, but more severe cases might require surgical repair.

Varicocele

A varicocele is a swollen collection of veins in your scrotum. It doesn’t always cause symptoms. When it does, symptoms include:

  • a dull, aching pain in your scrotum
  • pain that gets worse throughout the day
  • pain that starts to go away when you lie down
  • a scrotum that may feel like a “bag of worms”

You can have a varicocele your entire life and never need treatment. However, they can sometimes cause infertility or testicular shrinkage, so it’s best to have it checked out by your doctor.

Spermatocele

A spermatocele, or spermatic cyst, happens when a fluid-filled sac forms in the epididymis. These cysts aren’t cancerous or life-threatening, but they can cause pain and discomfort if they’re large.

Larger, more painful spermatoceles may need to be removed with surgery.

Testicular torsion

Testicular torsion means that your testicle has rotated in the scrotum. This twisting of the spermatic cord cuts off blood supply, nerve function, and sperm transport to your testicle. This condition is considered a medical emergency.

Symptoms of testicular torsion include:

  • severe scrotum pain and swelling
  • testicle swelling
  • lower abdomen pain
  • nausea and vomiting
  • testicle feeling higher or out of place
  • urinating more than usual

Seek emergency medical care for any of these symptoms.

Several things may increase the risk of testicular torsion, including:

  • injury to the scrotum
  • exercising too long or hard
  • free movement of the testicle in the scrotum caused by a genetic condition

Testicular torsion occurs more frequently in young children, teens, and young adults. Your doctor can temporarily treat testicular torsion by repositioning the testicle by hand. However, it frequently reoccurs. Experts surgery to permanently fix the problem, ideally within 12 hours from the start of symptoms.

Epididymitis

Epididymitis happens when the epididymis becomes infected or inflamed. It’s often the result of a sexually transmitted infection (STI), such as chlamydia or gonorrhea.

Symptoms of epididymitis can include:

  • scrotum or testicle pain or tenderness
  • warmness or redness in your scrotum
  • unusual fluid coming from your penis
  • frequent or painful urination
  • bloody semen
  • fever

Depending on the type of infection, you may need to take antibiotics or antiviral medication.

Orchitis

Orchitis refers to an infected or inflamed testicle. Like epididymitis, orchitis often results from an infection caused by an STI. Other causes can include tuberculosis, viruses like mumps, fungi, and parasites, along with other diseases that lead to inflammation.

Orchitis symptoms include:

  • testicular pain and tenderness
  • swollen testicle
  • fever
  • nausea
  • vomiting
  • feeling significantly ill

Treatment depends on the cause. Ultrasound of the scrotum and testicles can help determine the diagnosis and severity of the condition. Serious infections may require hospitalization or surgery.

Testicular cancer

Testicular cancer happens when cells abnormally multiply within the tissue of your testicles. It commonly starts in the cells that make sperm.

The cause of testicular cancer isn’t always clear. According to the , testicular cancer is the most commonly diagnosed cancer in males between the ages of 15 and 44.

Symptoms of testicular cancer can include:

  • lump in your testicle
  • feeling of scrotum heaviness
  • fluid buildup in your scrotum
  • testicular pain
  • abdomen or back pain
  • swollen or tender breast tissue

Treatment depends on your stage of cancer. Sometimes, your doctor will surgically remove the testicle. Radiation therapy or chemotherapy may also be part of the treatment plan. Stem cell transplant may also be used.

See your doctor if you notice any of the following common symptoms in your scrotum, testicles, or genital area:

  • mild or severe pain that lasts a long time
  • groin pain with activity
  • swollen areas
  • redness, rashes, or sores
  • feeling of heaviness
  • tender areas
  • severe pain in your scrotum that happens without warning
  • urinating more than usual
  • blood in your urine or semen
  • discharge or drainage from the penis

Also see your doctor if you notice pain in your lower abdomen or back, or extra breast tissue growth.

Here are some lifestyle tips for keeping your scrotum in good health:

  • Do a monthly testicular self-exam. Roll each testicle around in your scrotum using your fingers. Check for lumps and swollen or tender areas.
  • Bathe regularly. Take a shower or bath regularly to keep your entire genital area clean. This reduces your risk of skin infections that can cause other complications. Keep your penis and scrotal area dry after bathing. Moisture trapped in the area can quickly become a breeding ground for fungus.
  • Wear loose, comfortable clothing. Try to avoid wearing tight underwear and pants. Allow your scrotum to hang naturally from your body to help keep the scrotal temperature low and prevent injury.
  • Wear protection when you have sex. Wear a condom when doing any kind of sexual activity involving your penis. This helps to prevent sexually transmitted infections that affect your scrotum and testicles, as well as your partner.
  • Trim instead of shaving. If hair management is important to you, trimming rather than shaving or other complete hair removal systems is least likely to cause skin irritation, allergic reactions, trauma, or infections.