A retractile testicle is a testicle that may move back and forth between the scrotum and the groin. When the retractile testicle is in the groin, it might be easily guided by hand into its proper position in the scrotum — the bag of skin hanging behind the penis — during a physical exam. Upon release, the testicle will remain in the proper position at least temporarily.

For most boys, the problem of a retractile testicle goes away sometime before or during puberty. The testicle moves to its correct location in the scrotum and stays there permanently.

Sometimes the retractile testicle remains in the groin and is no longer movable. When this happens, the condition is called an ascending testicle or an acquired undescended testicle.

Testicles form in the abdomen during fetal development. During the final months of development, the testicles gradually descend into the scrotum. If this descent isn't completed at birth, the testicle usually descends within a few months. If your son has a retractile testicle, the testicle originally descended as it should, but doesn't remain in place.

Symptoms of a retractile testicle include:

• The testicle may be moved by hand from the groin into the scrotum and won't immediately retreat to the groin.
• The testicle might spontaneously appear in the scrotum and remain there for a time.
• The testicle might spontaneously disappear again for a time.

Retractile testicle is different from undescended testicle (cryptorchidism). An undescended testicle is one that never entered the scrotum.

When to see a doctor

During regular well-baby checkups and annual childhood checkups, a healthcare professional will examine the testicles to determine if they're descended and appropriately developed. If you believe that your son has a retractile or ascending testicle — or have other concerns about the development of his testicles — see his care professional. The care professional will tell you how often to schedule checkups to monitor changes in the condition.

An overactive muscle causes a testicle to become a retractile testicle. The cremaster muscle is a thin pouch-like muscle in which a testicle rests. When the cremaster muscle contracts, it pulls the testicle up toward the body. The cremaster reflex can be stimulated by rubbing a nerve on the inner thigh and by emotion, such as fear and laughter. The cremaster is also activated by a cold environment.

If the cremaster reflex is strong enough, it can result in a retractile testicle, pulling the testicle out of the scrotum and up into the groin.

There are no known risk factors for retractile testicles.

Retractile testicles are generally not associated with complications, aside from a greater risk of the testicle becoming an ascending testicle.

If your son has a testicle not located in the scrotum, his doctor will determine its location in the groin. Once it's located, the doctor will attempt to guide it gently into its proper position in the scrotum.

Your son may be lying down, sitting or standing during this examination. If your son is a toddler, the doctor might have him sit with the soles of his feet touching and knees to the sides. These positions make it easier to find and manipulate the testicle.

If the testicle is a retractile testicle, it will move relatively easily and won't immediately move up again.

If the testicle in the groin immediately retreats to its original location, it's most likely an undescended testicle.

Retractile testicles don't require surgery or other treatment. A retractile testicle is likely to descend on its own before or during puberty. If your son has a retractile testicle, a healthcare professional will monitor any changes in the testicle's position in annual evaluations to determine if it stays in the scrotum, remains retractile or becomes an ascending testicle.

If your son has a retractile testicle, he might be sensitive about his appearance. To help your son cope:

• Explain in simple terms what a retractile testicle is.
• Remind him that there's nothing wrong with him.
• Explain that the position of the testicle is something you, your son and his doctor will pay attention to and fix, if necessary.
• Help him practice a response if he's teased or asked about the condition.

A primary healthcare professional usually can diagnose a retractile testicle. However, if there is any question about the diagnosis or need for immediate treatment, you might be referred to a doctor who specializes in urinary disorders and problems with male genitals in children, called a pediatric urologist.

Be prepared to answer the following questions on your child's behalf or to help him answer questions:

• Were both testicles previously identified as descended in a well-baby or annual exam?
• When did you notice the absence of the testicle in the scrotum?
• Have you observed this before?
• Has your child experienced any pain in his testicles or groin?
• Has your son ever been treated for a hernia?
• Has your son experienced any trauma to his genitals or groin?