Definition

Undescended testis, or cryptorchidism, is a condition in which the testicle (testis) fails to descend to its normal position (the scrotum) from the abdomen before birth. Typically, only one testicle fails to descend in cryptorchidism, but in about 10% of cases, both testicles do not descend.

In most cases, the testicle will eventually descend to its normal position within the first few months of life. About 3% of full-term male babies are born with an undescended testis, and this number decreases to 1% in babies aged 6-12 months. Thirty percent of premature male babies are born with one or both testicles not descended into the scrotum. If they do not descend within a prolonged period, surgical procedures can be considered a treatment option.

Causes

During fetal development, the testes originate within the abdomen. Towards the end of gestation, typically in the last few months, they embark on a journey from the abdomen to the scrotum through a passage known as the inguinal canal, nestled in the groin fold. However, this natural descent is hindered or interrupted in undescended testis.

The exact cause of undescended testis, especially in full-term babies, is still not fully understood. It is suspected that there is a combination of genetic factors, the mother's health during pregnancy, and various environmental factors. The combination of these factors can disrupt hormones and nerve activity, causing physical changes that may interfere with the development and descent of the testicles.

Risk factor

Factors that can increase the risk of undescended testis in newborn babies include:

• Low birth weight.
• Smaller umbilical cord (placenta).
• Premature birth.
• Mother being overweight (obesity) during pregnancy.
• Mother having diabetes during pregnancy.
• Family history of undescended testis or other developmental disorders of the reproductive organs.
• Presence of fetal conditions that can inhibit growth, such as Down syndrome or abdominal wall defects.
• Alcohol consumption during pregnancy (≥5 drinks per week).
• Smoking or exposure to cigarette smoke during pregnancy.
• Exposure to pesticides or harmful chemicals during pregnancy.
• Preeclampsia (pregnancy complication).
• In vitro fertilization.

Symptoms

The main sign of an undescended testis is the inability to see or feel the presence of the testicle in its scrotal sac, where the testis is usually located. Undescended testis can occur in one or both testicles, although it often occurs in the right testicle. Most babies and children with this condition do not show specific symptoms or complaints. Sometimes, a hernia (protrusion of an organ) may be found in the groin fold.

Diagnosis

Doctors typically inquire about parental concerns, the child's birth history, and the family's medical history. They also perform a physical examination by observing and palpating the child's scrotal area, abdomen, and pelvis. Further diagnostic tests may be recommended if indicated. Although not commonly used, ultrasound examination is one such test. However, its sensitivity and specificity in locating the testicle are only about 45% and 78%, respectively.

Management

Newborn babies with undescended testis are generally observed during the first few months of their lives. In most cases, if there are no issues, the testicle will descend within the first three months.

For children aged 6-18 months with persistently undescended testicles, doctors may recommend a surgical procedure to return the testicle to its normal position in the scrotal sac. According to expert opinion, surgical management is recommended to be performed early, ideally when the child is 6 months old, to optimize testicular growth and fertility. In some cases, the testicle may not develop properly, be abnormal, or be necrotic, requiring the removal of such testicular tissue.

During the surgical procedure (orchidopexy), the doctor manipulates the testicle into the scrotum and sutures it in place. This procedure can be performed using laparoscopy or open surgery. The timing of the surgery depends on several factors, including the child's health and the complexity of the procedure. Early surgical intervention reduces the risk of complications later on.

After surgery, the doctor monitors the testicle to assess its continued development, normal function, and position. Testicular prosthesis may be considered if the testicle cannot be saved and is absent, aiming to provide a normal appearance to the scrotum.

Complications

For the development and normal function of the testicles, a slightly cooler temperature than the normal body temperature is required. The scrotal sac provides this lower temperature as it is outside the body.

Complications that can occur when the testicles are not in their proper location include:

• Testicular cancer

Testicular cancer usually originates from cells inside the testicle that produce immature sperm. The exact cause of cells mutating into cancer cells is still not fully understood. Men who have had undescended testicles are at a higher risk of developing testicular cancer. This risk increases if the testicle is located in the abdomen rather than the groin fold. It also becomes higher if both testicles do not descend.

• Fertility issues

Low sperm count and quality, as well as decreased fertility, are more common in men with a history of undescended testicles. This can result from disruptions in testicular development. Fertility may be further impaired if this condition is not addressed for a prolonged period.

• Testicular torsion

Testicular torsion occurs when the spermatic cord, which contains blood vessels, nerves, and the duct that carries semen from the testicle to the penis, becomes twisted. This twisting cuts off blood flow to the testicle. If not promptly treated, it can lead to permanent testicular damage. Testicular torsion occurs 10 times more frequently in men with undescended testicles than those with normal testicles.

• Injury

If the testicle is in the groin fold, it can sustain damage due to pressure from the pubic bone.

• Inguinal hernia

The testicle may fail to descend into the scrotal sac and move into the groin fold area instead.

Prevention

There is no known way to prevent undescended testicles. However, as a parent, you can observe and feel if your child's scrotal sac remains empty after 3-6 months since birth. Early detection can lead to early treatment for your child.

When to see a doctor?

Undescended testicles are usually detected at birth during a newborn examination. If your child has undescended testicles, ask the doctor how often your child should undergo examinations. If the testicle has not descended into the scrotal sac by the time the child reaches four months, it will unlikely descend independently.

If you notice any changes or abnormalities in your child's genitalia, it is advisable to consult a doctor promptly.

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