A retractile testicle is a testicle that may move back and forth between the scrotum and the groin. When the retractile testicle is residing 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.
Signs and 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, your son's doctor will examine your son's 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 doctor. He or she 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.
Retractile testicles are generally not associated with complications, aside from a greater risk of the testicle becoming an ascending testicle.