Definition

Under normal circumstances, the developing testes of a fetus grow within the abdomen. Just prior to birth, the testicles move downward through the inguinal canal and into the scrotum. In the cases of undescended testes, the testicles stay within the abdomen, even after birth.

Undescended Testis

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Causes

Undescended testes are a congenital problem, meaning they are present at birth. The exact cause is not known, but inheritance may play a role. There may be some hormonal abnormality associated with the development of undescended testes. Twisting (torsion) of the testes within the abdomen during fetal development may cause injury or loss of the testes. “Ascending” undescended testes may occur in boys during childhood when a previously descended testis moves out of the scrotum into a low inguinal position.

Risk Factors

The following factors increase your child’s chance of having undescended testes. If he has any of these risk factors, tell your doctor:

• Prematurity
• Low birth weight
• Twin gestation
• Down syndrome (fetus) or other chromosomal abnormality
• Gestational diabetes mellitus
• Prenatal alcohol exposure
• Hormonal abnormalities (fetus)
• Toxic exposures in the mother
• Mother younger than 20
• A family history of undescended testes

Symptoms

• Undescended testes cause no symptoms. They can, however, become twisted inside the abdomen (a condition called “testicular torsion”), a problem that requires surgery.
• Grown men with undescended testes may have low sperm counts resulting in infertility, and are at increased risk for hernia and testicular cancer because of their untreated undescended testes.
• Increased risk of hernia
• Increased risk of testicular cancer, even after surgical correction, and even in the other, properly descended testicle
• In a similar condition called retractile testes (also known as “hypermobile” testes), descended testes slip easily back and forth between the scrotum and the abdomen. Retractile testes do not lead to cancer or other complications. They usually stop retracting by puberty and do not require surgery or other treatment.

Diagnosis

Your doctor will ask about your symptoms and medical history, and perform a physical examination . A diagnosis of undescended testes is usually made by a pediatrician based on the fact is one or both of the child’s testes cannot be felt within his scrotum. Additional tests may include the following:

• Radiographic imaging— MRI and CT have been shown to be more accurate than ultrasound in identifying intra-abdominal testes.
• Laparoscopy —a surgical procedure using a tiny video camera inserted within a small “keyhole” incision in the scrotum. This can identify the presence of a testicle within the abdomen, and can potentially then be used as treatment, as well.

Treatment

Talk with your doctor about the best treatment plan for your child. Treatment options include:

• Giving the problem time to go away on its own—In most children, this happens by four months of age, without any other intervention.
• Hormone therapy using human chorionic gonadotropin (HCG) is used infrequently.
• If the testes do not descend on their own, the problem can be repaired by a surgery called an orchiopexy. This is done while your child is asleep under anesthesia. The surgery may be performed through a traditional open incision, or through “keyhole” laparoscopic surgery

Prevention

There is no known way to prevent undescended testes. Preventable complications of undescended testes may occur, however, as your child grows and matures. These include:

• Infertility or testicular cancer in adulthood.
• Injury to the undescended testes.
• Emotional stress—While surgery usually results in a normal appearing scrotum, the undescended testis is sometimes smaller than the normal one. If your son becomes concerned about this as an older child or adolescent, a prosthesis (artificial replacement) can be placed in the scrotum.