Get to Know Your Scrotum a Little Better

Walking into a cold pool on a hot day is an enjoyable experience from the toes to the thighs. However, there's always a moment about 3 feet up when many guys tense up in anticipation. They prepare for the imminent, uncomfortable instant when the water rises to meet their waist and their scrotum takes the plunge.

Yes, the scrotum is incredibly sensitive, but it's allowed to be. It has an important job: protecting your testicles, the epididymides and the vasa deferentia, which move sperm along to your penis when the time comes.

If, as biologist Charles Darwin suggested, a species' biological purpose is reproduction, then the scrotum might be the most important part of the male body. Yet most men don't actually know much about their scrotum, beyond protecting it from a blow.

Avoiding physical trauma is a good starting place, but you should know some other important facts about your scrotum.

It's a multilevel, multipurpose house

"The scrotum houses two of the most important organs to us: our testicles," said Nannan Thirumavalavan, M.D., chief of male reproductive and sexual health at University Hospitals in Cleveland. "The reason it's not the same way that women have ovaries on the inside is that testicles need a cooler temperature to be able to make sperm and function well."

As the house for your testicles, the scrotum regularly shrinks and lengthens to regulate the temperature of the testes. When you're hot, it lengthens to keep the testicles away from the body; when you're cold, it shrinks to use your body warmth. Men most often notice this change during sudden temperature shifts—hence, the hesitation when wading into cold water.

In addition to the testicles, the scrotum also contains the epididymides (each testicle has one), the structure that stores sperm as they mature, and part of the vas deferens—again, one in each testicle.

The scrotum is wrinkly for a reason

Most people would probably agree scrotums look strange. There is a reason for that, and it has to do entirely with how the scrotum shrinks and grows to maintain testicle temperature.

"Your scrotum has a muscle underneath it called a subcutaneous muscle, meaning it spans the skin, but specifically, the one in your scrotum is the dartos muscle," Thirumavalavan said. "That and the cremaster muscle around the testicle itself are responsible for the testicle rising and falling and the scrotum getting tighter in response to the environment. It's very adaptable as a structure."

Your scrotum starts its life inside your abdomen

Most men, likely in their teen years, heard someone insultingly ask, "Have your balls dropped yet?" While many people mistakenly think this action happens during puberty—therefore separating a "boy" from a "man"—it actually happens much sooner.

"In utero, your testicles are in your belly, and then they slowly drop and come out to where they are," Thirumavalavan said. "But sometimes in childhood, kids have a condition where it's not all the way out, and they sometimes need surgery to bring the testicles all the way down to where they're supposed to be."

This condition is known as undescended testes, or more scientifically, cryptorchidism. Generally, if the testicles don't drop within three months of birth, doctors suggest surgery. Earlier treatment of the issue reduces the risk of infertility and testicular cancer later in life.

Lots of things can happen to the scrotum

Given how important the scrotum is to sexual function, men should understand the importance of when and how things can go wrong.

Of course, many issues can be felt. For example, Thirumavalavan said men can usually feel cysts behind the epididymis, though most of the time these cysts aren't particularly harmful or a cause for concern.

"Another common thing we see is what's called a varicocele," Thirumavalavan said. "Basically, there are veins that drain the testicles and these veins can become dilated and big. Classically, they're described as looking like a bag of worms in the testicles. So a lot of guys will feel this, too. It's pretty common. About 1 in 8 guys will have one by the age of 18."

He added that a varicocele typically doesn't affect a man's life, but in extreme cases, it can be a source of pain and, potentially, infertility.

Aram Loeb, M.D., a University Hospitals urologist in Parma, Ohio, identified other common problematic occurrences in the scrotum, including epididymo-orchitis, an infection of the testicles or epididymis; a hydrocele, which is fluid around the testicles; testicular tumors; and testicular torsion, an incredibly painful twisting of the spermatic cord that requires immediate attention.

"However, probably more common than all [of these] is to have a 'normal' evaluation with no clear source of pain," Loeb said. "This often gets clumped into the diagnosis of 'chronic prostatitis.' Men are often treated numerous times with antibiotics only to have the symptoms return. This can be extremely frustrating and demoralizing for men as they get passed around to different physicians with no resolution of their pain."

If sports are part of your regular routine, wear a cup.

"Yes, it's annoying to wear a cup," Thirumavalavan said. "It makes it harder to run, but you can get some pretty bad injuries to the testicles during sports, so protect them."

Examine the scrotum's residents

Causes of genital pain can be difficult to pinpoint by yourself, so see a doctor whenever something doesn't feel right. However, both Thirumavalavan and Loeb recommend men perform regular testicular self-exams to identify signs of trouble early.

"I think it's hard for the average person to know the difference between a testicular mass and a cyst behind the testicle that isn't dangerous," Thirumavalavan said. "So I would say if there's any sort of concern or question, you should go see somebody who can give you a better and more definitive answer. You'd rather be more careful than less."

"You don't need to be a doctor or even necessarily know what you are feeling for," Loeb added. "But more importantly, you need to understand your 'normal' and then be able to identify if anything is different or in pain."

Beyond self-exams, making healthy lifestyle choices can undoubtedly encourage proper genital health. Don't smoke, eat a healthy diet, exercise regularly, stay hydrated and get plenty of sleep.