Questions and Answers About Undescended Testicles in Baby Boys

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As a pediatric urologist, I diagnose a newborn baby boy with an undescended testicle nearly every day. Undescended testicles are a very common condition occurring in nearly 5 percent of newborn boys. Many parents are thankful to know that this condition, also known as cryptorchidism, is benign, but it brings up many questions: Will he need surgery? Does this mean that my son is missing a testicle? What about his ability to have children one day? The answers to these questions are more easily understood with a little background on how testicles form and descend when the baby is in his mother’s womb.

Testicles develop in the abdomen of the unborn male and descend from the abdomen down into the scrotum during the third trimester. Cryptorchidism occurs when a testicle fails to complete its descent from the abdomen to the scrotum. Cryptorchidism is rarely associated with other diagnoses and is not a sign of any other syndromes. Upon first examination, I typically don’t even need to run any additional tests.

Cryptorchidism can usually be broken up into two categories. With patients in the first category, both testicles are present on examination, but at least one of them can be felt somewhere between the groin and the scrotum. These testicles may descend on their own for up to one year and typically no surgery is recommended until we are certain that the testicle will not complete its descent on its own. If we do need to perform surgery, the success rate is high, greater than 95%.

When I examine patients in the second category, their testicles cannot be felt on examination. If these testicles don’t descend to a position where they can be felt by six months of age, there is little chance that they will spontaneously descend to the scrotum. At this point, I recommend laparoscopic surgery.

In nearly one-third of these cases where a testis is non-palpable by six months, the child is actually missing that testicle. This is often referred to as a vanishing testicle that most likely twisted and did not form due to lack of blood supply at some point during the descent from the abdomen. The laparoscopic approach allows us to determine if a testicle is present and to bring it down during the same surgery. This is performed in the outpatient surgery and has a slightly lower success rate ranging from 80 to 90 percent.

What Are the Risks?

Questions that I often get asked of parents whose children experience cryptorchidism usually include, “What are the risks for infertility?” and, “Is there an increased risk for developing testicular cancer?”

Studies suggest that there is a reduction in sperm-producing cells within the testicle starting as early as six months of age and this reduction is accelerated the higher the testicle was before it descended. Infertility is nearly a certainty in patients where both undescended testicles are left untreated. However, when surgery is performed in childhood, this risk can be reduced by half. Children with only one undescended testicle have only a 13 percent risk of infertility.

Undescended testicles are associated with a five-fold increase in the development of a testicular malignancy over a patient’s lifetime. Similarly, with a higher location of the undescended testicle the risk of malignancy increases, i.e. abdominal testicles have a higher rate of developing a tumor than groin testicles. However, if surgery is performed to bring these testicles down prior to puberty, this risk may be reduced by more than half. 

Remember, undescended testicles are quite common. Often these testicles descend on their own, but if not, a pediatric urologist can help. Early intervention may reduce both the risk of infertility and the future development of testicular cancer, so if you need help, don’t delay.

Joe Molitierno, MD is a board-certified Pediatric Urologist who trained at both UNC Chapel Hill and Emory Schools of Medicine. He has been practicing in the Charlotte area for over nine years. He is a partner with Pediatric Urology Associates, PA and is the director of the Nocturnal Enuresis and Wetting Treatment (NEWT) center, the Carolinas first pediatric voiding dysfunction center.  

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