Undescended Testicle: Causes, Surgery & Treatment Guide

What Is an Undescended Testicle?

An undescended testicle (cryptorchidism) is a condition where one or both testicles have not moved from the abdomen into the scrotum by the time of birth. It affects about 3% of full-term newborn boys and up to 30% of premature male infants, making it one of the most common congenital abnormalities in boys.

During normal fetal development, the testicles form inside the abdomen near the kidneys. As the fetus grows, the testicles gradually descend through the inguinal canal into the scrotum. This journey typically completes during the third trimester of pregnancy, which is why premature babies are at higher risk of having undescended testicles since this process may not have finished before birth.

The condition can affect one testicle (unilateral, which accounts for about 70% of cases) or both testicles (bilateral, about 30% of cases). When both testicles are undescended, it's important to investigate for possible underlying hormonal or genetic conditions. The undescended testicle may be located anywhere along the normal path of descent, from the abdomen through the inguinal canal, or occasionally in an abnormal position altogether.

Understanding where the testicle is located helps determine the best treatment approach. In most cases, the testicle can be felt in the groin area during physical examination. When it cannot be felt (known as a non-palpable testicle), further investigation may be needed to determine if the testicle is located in the abdomen, is very small, or is absent.

Why does it matter?

The scrotum provides a slightly cooler environment than the rest of the body, which is essential for normal sperm production. When a testicle remains in the abdomen or groin, it's exposed to higher temperatures that can damage the cells responsible for producing sperm. This is why timely treatment is so important for preserving fertility. Additionally, an undescended testicle has a slightly higher risk of developing testicular cancer later in life, though this risk is significantly reduced with early surgical treatment.

Types of undescended testicle

Healthcare providers classify undescended testicles based on where they are located and whether they can be felt during examination. A palpable undescended testicle can be felt somewhere along the path from the abdomen to the scrotum, most commonly in the inguinal canal (groin area). A non-palpable undescended testicle cannot be felt and may be located inside the abdomen, may be very small (atrophic), or may be absent altogether. This distinction is important because it affects the diagnostic approach and surgical technique.

What Causes an Undescended Testicle?

The exact cause of undescended testicle is often unknown, but risk factors include premature birth, low birth weight, family history, and certain genetic or hormonal conditions. The condition results from an interruption in the normal process of testicular descent during fetal development.

The process of testicular descent is complex and involves a coordinated interplay of hormones, genetic factors, and anatomical structures. While researchers have identified several factors associated with undescended testicles, in many cases the specific cause cannot be determined. Understanding the risk factors can help healthcare providers identify babies who may need closer monitoring.

Premature birth is the most significant risk factor for undescended testicle. Since testicular descent typically occurs during the third trimester, babies born before 37 weeks of gestation haven't had enough time for this process to complete. The earlier the baby is born, the higher the likelihood that the testicles have not yet descended. For very premature infants (born before 28 weeks), the rate can be as high as 100%.

Low birth weight, even in full-term babies, is also associated with increased risk. This may be related to factors that affect overall fetal growth and development. Studies have shown that babies weighing less than 2500 grams at birth have a significantly higher incidence of undescended testicles compared to those with normal birth weight.

Genetic and hormonal factors

Family history plays a role in some cases. If a father or brother had an undescended testicle, the risk is increased. This suggests genetic factors are involved, though the specific genes responsible have not been fully identified. Research has found that mutations in certain genes involved in hormone signaling pathways may contribute to the condition.

Hormonal factors during pregnancy may also influence testicular descent. The process depends on adequate production and response to certain hormones, particularly testosterone and a hormone called insulin-like factor 3 (INSL3). Any disruption in these hormonal signals during fetal development could potentially interfere with normal descent.

Environmental factors

Some studies have suggested that exposure to certain environmental chemicals during pregnancy may increase the risk of undescended testicle. These include substances called endocrine disruptors, which can interfere with hormone function. However, the evidence for specific environmental causes remains inconclusive, and more research is needed in this area.

Maternal health factors during pregnancy have also been studied. Gestational diabetes, smoking during pregnancy, and alcohol consumption have all been investigated as potential risk factors. While some associations have been found, they are generally weaker than the established risk factors of prematurity and low birth weight.

How Is an Undescended Testicle Diagnosed?

Undescended testicle is diagnosed primarily through careful physical examination by a healthcare provider. The examination is typically performed shortly after birth, at routine health check-ups, and ideally when the baby is calm and warm. Imaging studies like ultrasound may be used in some cases, though they have limitations.

The physical examination is the most important diagnostic tool for identifying undescended testicles. Healthcare providers are trained to check that both testicles are present in the scrotum as part of routine newborn examinations. They will gently palpate the scrotum and groin area to feel for the testicles, assess their size, and determine their position.

For the most accurate examination, the baby should be relaxed and comfortable. The room should be warm because cold temperatures can cause the cremaster muscle to contract and pull the testicles up toward the body. If a testicle is not found in the scrotum, the healthcare provider will carefully examine the inguinal canal and surrounding areas to determine if it can be felt elsewhere.

It's important for parents to also learn how to check that their baby's testicles are in the scrotum. This can be done during bath time when the baby is relaxed and the warm water helps the testicles descend. If you cannot feel both testicles in the scrotum, bring this up with your healthcare provider at your next visit.

When to seek medical advice

You should contact your healthcare provider if you cannot feel that both testicles are present in your baby's scrotum. While it's normal for testicles to move up and down somewhat (especially in cold conditions or when the baby is upset), you should be able to feel them in the scrotum when your baby is calm and warm. Your healthcare provider can perform a thorough examination and determine if referral to a specialist is needed.

Imaging and additional tests

In many cases, no imaging is required because an experienced healthcare provider can locate the testicle through physical examination alone. However, when the testicle cannot be felt (non-palpable), additional investigations may be helpful. Ultrasound can sometimes locate a testicle in the inguinal canal, though its usefulness for finding testicles in the abdomen is limited.

For truly non-palpable testicles, laparoscopy (a minimally invasive surgical procedure using a small camera) is often the most reliable way to determine if the testicle is inside the abdomen, is absent, or is atrophic (very small and non-functional). This diagnostic procedure can often be combined with the surgical treatment in the same session.

How Is an Undescended Testicle Treated?

The primary treatment for undescended testicle is surgery called orchiopexy, which moves the testicle into the scrotum and secures it in place. Current guidelines recommend this surgery be performed between 6 and 12 months of age, and no later than 18 months, to optimize fertility outcomes and reduce cancer risk.

The decision about when and whether to treat depends on several factors. For newborns, healthcare providers typically recommend a period of watchful waiting during the first six months because many testicles will descend on their own during this time. Studies show that approximately 75% of undescended testicles at birth will spontaneously descend by 3 months of age, with most doing so by 6 months. If the testicle has not descended by 6 months, it is very unlikely to do so on its own.

Once it's clear that spontaneous descent won't occur, surgical treatment is recommended. The timing of surgery has been a subject of much research and discussion in the medical community. Current evidence strongly supports early surgical intervention, with most guidelines recommending surgery between 6 and 12 months of age. Earlier surgery is associated with better preservation of testicular tissue and improved fertility outcomes.

Orchiopexy surgery explained

Orchiopexy is the standard surgical procedure for correcting an undescended testicle. The surgery is typically performed as an outpatient procedure, meaning the child goes home the same day. The operation usually takes about 30 minutes, though this can vary depending on the location of the testicle and individual circumstances.

The child is given general anesthesia so they sleep through the entire procedure. Parents are usually allowed to stay with their child until they fall asleep. The surgeon makes a small incision in the groin area to access the inguinal canal where the testicle is typically located. The testicle is carefully freed from surrounding tissue while preserving the blood vessels and vas deferens (the tube that carries sperm).

Once mobilized, the testicle is guided through the inguinal canal into the scrotum, where a small pouch is created to hold it in place. The testicle is secured with stitches to prevent it from moving back up. The incisions are closed with dissolvable stitches and covered with dressings. Most surgeons use techniques that result in minimal visible scarring.

Laparoscopic surgery for intra-abdominal testicles

When the testicle cannot be felt during examination and is suspected to be inside the abdomen, laparoscopic surgery may be necessary. This minimally invasive technique uses small incisions and a camera to locate the testicle inside the abdomen. If the testicle is found, it can sometimes be brought down into the scrotum in the same procedure.

In some cases, when the testicle is located high in the abdomen, a two-stage procedure called the Fowler-Stephens orchiopexy may be needed. In the first stage, the blood vessels supplying the testicle are divided to allow other blood vessels to take over the blood supply. Several months later, a second surgery is performed to bring the testicle into the scrotum.

What to Expect After Surgery?

Recovery after orchiopexy is typically quick and uncomplicated. Most children go home the same day, experience mild discomfort for a few days, and can return to normal activities within a week. The scrotum may be swollen and bruised but heals well with proper care.

After the surgery is completed, your child will wake up in the recovery area. Parents are typically brought to be with their child as soon as they start waking up. It's normal for children to be somewhat groggy, irritable, or nauseous immediately after anesthesia. The medical team will monitor your child and provide medication if needed to control any discomfort or nausea.

Most children can leave the hospital a few hours after surgery once they're awake, comfortable, and can drink fluids. Before leaving, you'll receive detailed instructions about caring for your child at home. The medical team will explain what to watch for and when to contact them if you have concerns.

Caring for your child at home

In the first few days after surgery, it's normal for the scrotum to be swollen, bruised, and tender. On lighter skin, the scrotum may appear blue or purple. On darker skin, color changes may be less noticeable. The swelling typically peaks around 24-48 hours after surgery and then gradually improves over the following week.

Your child can shower the day after surgery, but you should avoid baths until the wound has healed, usually about one week. Keep the outer dressing clean and dry. If it becomes wet or dirty, you can replace it. There are typically small adhesive strips (steri-strips) directly over the incision - leave these in place until they fall off on their own.

Pain management is important for your child's comfort and recovery. Age-appropriate over-the-counter pain medications such as acetaminophen (paracetamol) or ibuprofen are usually sufficient. Your healthcare provider will give you specific dosing instructions based on your child's weight and age. Most children need pain medication for only a few days.

Returning to normal activities

Children recover remarkably quickly from this surgery. Within a few days, most children are moving and playing normally. They can typically return to daycare or preschool once they're comfortable enough to participate in regular activities, usually within a few days to a week. However, strenuous activities, rough play, and activities that could injure the surgical area should be avoided for about 2-4 weeks.

Follow-up care

Your child will have a follow-up appointment approximately 6 months after surgery. During this visit, the healthcare provider will examine your child to ensure that the testicle remains in its proper position in the scrotum and that healing has occurred normally. This follow-up is important for confirming the success of the surgery and addressing any concerns.

What Are the Possible Complications?

Surgical complications from orchiopexy are uncommon, with success rates around 98%. Possible complications include infection, bleeding, and very rarely, damage to the blood supply of the testicle. Long-term risks of untreated undescended testicle include reduced fertility and slightly increased cancer risk.

Orchiopexy is a well-established, safe procedure with excellent outcomes when performed by experienced surgeons. However, like any surgery, there are potential risks that parents should understand. Discussing these with your surgeon before the procedure can help you make an informed decision and know what to watch for afterward.

Surgical complications

Infection at the surgical site is possible but uncommon, occurring in less than 1% of cases. Signs of infection include increasing redness, swelling, warmth, or discharge from the wound, often accompanied by fever. Most surgical site infections can be treated with antibiotics.

Bleeding and hematoma (collection of blood) can occur but are also rare. Some bruising and swelling is normal, but if the scrotum becomes dramatically swollen or if there is active bleeding from the incision, contact your healthcare provider.

In rare cases (approximately 1-2%), the blood supply to the testicle may be compromised during surgery, potentially leading to testicular atrophy (shrinkage) or loss. This risk is higher when the testicle is located high in the abdomen and requires more extensive mobilization. Surgeons take great care to preserve the blood supply, but this is a recognized risk of the procedure.

Long-term complications of untreated undescended testicle

If an undescended testicle is not treated, there are important long-term health implications. Understanding these risks highlights why early surgical correction is recommended.

Fertility concerns: The most significant long-term risk of untreated undescended testicle is reduced fertility. The higher temperature inside the body damages the cells that produce sperm. Studies show that men with a history of bilateral (both sides) untreated undescended testicles have significantly higher rates of infertility. Even unilateral cases can affect sperm parameters. Early surgical correction, especially before 12 months of age, gives the best chance for normal fertility.

Testicular cancer risk: Men who had an undescended testicle have approximately 2-8 times higher risk of developing testicular cancer compared to the general population. However, it's important to put this in perspective - testicular cancer is rare overall, so even with increased risk, the absolute likelihood remains low. Early orchiopexy appears to reduce this risk, which is one reason why surgery is recommended in the first year of life. Even after successful surgery, men with a history of undescended testicle should be aware of the importance of testicular self-examination.

Testicular torsion: An undescended testicle may have increased mobility, which raises the risk of testicular torsion (twisting of the testicle on its blood supply). This is a medical emergency that causes sudden, severe scrotal or groin pain and requires immediate surgery. Orchiopexy reduces this risk by securing the testicle in the scrotum.

Frequently Asked Questions