What is Cryptorchidism (Undescended Testicle)?
Cryptorchidism is the medical term for when a boy is born with one or both testicles not in the scrotum. It’s the most common birth defect affecting the male genitals. Around 3% of full-term boys and 30% of premature boys are born this way. Usually, the testicles descend into the scrotum by the seventh month of fetal development, and most undescended testicles will descend on their own within the first three months after birth. After this period, only about 1% of boys still have this condition.
Doctors can usually feel (or palpate) the undescended testicles, which are often located near the groin but can also be in the abdomen or missing entirely. However, in about 20% to 30% cases, the testicles are not able to be felt.
If a testicle has not descended on its own by six months of age, it likely won’t without surgical intervention. In these cases, doctors will typically recommend a surgery known as an orchiopexy between six and 18 months of age. This procedure moves the undescended testicle into the scrotum.
The undescended testicle can have different characteristics and can be located anywhere along its normal descent pathway, including higher up in the abdomen or diverging from the usual pathway. In two-thirds of cases, only one testicle is affected.
Cryptorchidism comes with multiple long-term health risks if left untreated, including reduced fertility, a slightly increased chance of testicular cancer, an increased likelihood of the testicle twisting (torsion), hernias, and potential psychological issues related to the condition. If both testicles are undescended, there is a high risk of infertility. Also, men who had cryptorchidism as babies often have lower quality sperm as adults, likely due to changes in specific cells within the testicle.
In summary, cryptorchidism is a part of a group of male reproductive diseases related to certain disruptions in development before birth. It includes this condition, a condition impacting the urethra (hypospadias), testicular cancer, and decreased sperm quality, collectively known as testicular dysgenesis syndrome.
What Causes Cryptorchidism (Undescended Testicle)?
The normal drop of the testicles into the scrotum needs the hypothalamic-pituitary-gonadal axis, one of the key systems in the body responsible for producing hormones. There is an association noticed between testicles that don’t descend and the absence of an appendix testis, a small gland-like structure found alongside the testis. But, there’s still uncertainty about the exact role of this appendix testis in testicular descent.
The cause of undescended testes, also known as cryptorchidism, is often unexplained in newborn babies, making it a common but unpredictable birth abnormality. This condition could possibly be triggered by a mix of genetics, maternal health and habits, and elements of the environment that may interrupt the hormonal and physical changes essential for testicular development and descent.
The main risk factor for undescended testes is low birth weight, with family history coming next. Other probable risk factors include a wide range of things linked with their mother’s health and environment such as: consuming 5 or more alcoholic beverages a week when pregnant, exposure to certain chemicals, smoking, having certain congenital syndromes like Down Syndrome, usage of certain cosmetics, exposure to a compound called phthalate, history of undescended testes in the family, use of a common painkiller called ibuprofen, undergoing in vitro fertilization and having certain conditions like diabetes or obesity.
Moreover, there is an increased risk of undescended testes when the mother experiences preeclampsia, especially severe forms. Similarly, infants born prematurely (i.e., before the testicles descend), infants who are smaller than normal for their gestational age, and infants with lower placental weight are also at higher risk of this abnormality.
Risk Factors and Frequency for Cryptorchidism (Undescended Testicle)
Cryptorchidism, or undescended testicles, is seen in about 3% of full-term babies at birth. However, by the time they reach 6 months to 1 year old, the rate goes down to 1%. In the United States, the numbers are similar, and the rate globally also follows this pattern. However, for premature baby boys, the rate is quite a bit higher – about 30%. This means it’s really important to keep a close eye on how the testicles are developing in young boys, especially if they were born premature and might need treatment.
Cryptorchidism can also run in families. Between 1.5% and 4% of men who are fathers and 6% of men who are brothers to someone with cryptorchidism also have it. First-degree male relatives, meaning fathers, sons, and brothers, are somewhere between 0.5% and 1% likely to have cryptorchidism. It is also seen in 7% of brothers of boys whose testicles haven’t descended, highlighting the possibility that it can be genetic. Researchers are also looking into links between cryptorchidism and the developmental disorder, autism.
- Cryptorchidism is seen in about 3% of full-term newborns, but this decreases to 1% at ages 6 months to 1 year.
- In the US, the prevalence is similar, ranging from about 3% at birth to 1% from 1 year to adulthood.
- Worldwide, the prevalence starts at around 4% to 5% at birth, dropping to 1% to 1.5% at 3 months old, and decreasing to 1% to 2.5% at 9 months.
- 30% of premature male newborns experience cryptorchidism, highlighting the importance of monitoring testicular development in young boys and intervening when necessary.
- Approximately 1.5% to 4% of fathers and 6% of brothers of individuals with cryptorchidism also have it.
- About 0.5% to 1% of first-degree male relatives are likely to have cryptorchidism.
- Seven percent of brothers of boys with undescended testes also have cryptorchidism, suggesting a possible genetic link within families.
- Research is ongoing into the association between cryptorchidism and autism.
Signs and Symptoms of Cryptorchidism (Undescended Testicle)
An individual with cryptorchidism, or an undescended testicle, can usually be identified by the lack of a testicle in the scrotum. Other signs often include an inguinal hernia and fewer wrinkles or ridges on the scrotum. A complete physical examination of the groin and pelvic area is essential and can help determine whether the condition is simply a retractile testicle, which doesn’t usually need treatment.
People with undescended testicles may also experience some other issues. Here are a few associated with this condition:
- Infertility: Factors such as increased temperature, anatomical abnormalities like a disconnection between the testis and the epididymis, injuries during surgeries, and a higher presence of anti-sperm antibodies can contribute to reduced fertility in people with cryptorchidism. This is true whether both or just one of the testicles are affected. Roughly 10% to 30% of people with one undescended testicle may become infertile. In cases of untreated bilateral cryptorchidism, infertility rates can rise to 90%.
- Psychological Impact: Boys with this condition don’t have a higher chance of exhibiting gender-related disorders or effeminate traits. However, if family dynamics negatively impact their self-esteem, they may struggle with their self-image. Surgery to correct cryptorchidism can often help develop a healthy sense of masculinity.
- Cancer: The risk of testicular cancer is about thrice than that of the general population if the orchiopexy surgery is performed before puberty. This risk could increase fivefold or sixfold if the surgery is performed after puberty. Seminoma is the most common type of testicular cancer found in untreated undescended testes. Education about regular self-examinations for testicular cancer is essential for early detection and effective treatment.
Testing for Cryptorchidism (Undescended Testicle)
According to the American Urological Association’s guidelines, a trained provider can often locate more than 70% of missing testicles just by physical examination, leaving no need for imaging. In the other 30% of cases where the testicle is not able to be felt, it can be a challenge to prove whether the testicle is there or not and if it is, where it’s located.
While routinely using ultrasound may seem like the solution, it’s limited in how well it can locate missing testicles. Data shows that nearly half the boys with a missing testicle and a negative ultrasound end up having a testicle found in their abdomen. The use of computed tomography scans is limited because of the cost and the exposure to potentially harmful radiation. Magnetic resonance imaging tests, sometimes used with angiography, are more accurate, but they aren’t used often due to their high cost, limited availability, and need for anesthesia. So far, no imaging test can undoubtedly confirm the absence of a testis.
Analysing a patient’s karyotype – a display of their chromosomes – can help confirm or dismiss some primary issues with the development of an individual’s sexual characteristics. Hormone levels may verify whether testicles are functioning hormonally and therefore possibly worth preserving. In some cases, further testing is essential to identify any conditions that affect an individual’s sexual development.
When both testicles can’t be located, the condition requires additional evaluation to search for potential disorders of sexual development. Before this investigation is complete, any plans to perform a circumcision should be put on hold.
In some cases, individuals born with female genetics and a condition that makes the adrenal glands produce too much androgens (a type of hormone) may be initially misidentified as males with two missing testicles. It’s important to check for this condition by checking electrolyte levels, analysing the patient’s karyotype, and profiling their hormones.
The next step is to confirm whether testicular tissue is present. The presence of a specific hormone from the testicle would suggest that testicular tissue is present somewhere, possibly within the abdomen. Certain hormones can stimulate the production of other hormones and testosterone in the body. If the individual has male chromosomes, no detectable testes, increased levels of certain hormones, and no detectable levels of other hormones, they could be diagnosed as having no testicular tissue. Tests that were once performed have been replaced by more powerful tests. Where testicular tissue is thought to exist, a surgical procedure can be carried out to determine the location of the testicular tissue and decide on the best surgical approach.
Treatment Options for Cryptorchidism (Undescended Testicle)
Several respected medical guidelines, including those of the American Urological Association and others, suggest not using hormonal therapy for inducing the descent of a testicle. This is due to its low effectiveness and lack of long-term success. However, the American Pediatric Association does recommend hormones in cases where an undescended testis is associated with Prader-Willi syndrome. This is to avoid the risks of general anesthesia in infants with low muscle tone and high risk of respiratory issues. The most commonly used hormone in therapy is hCG, which has resulted in success rates varying between 5% and 50%.
Though hormonal treatment is often seen as a less expensive alternative to surgery with fewer possible complications, a recent study found it was no more effective than a placebo.
For babies born with undescended testes, surgical intervention is recommended between the ages of 6 and 18 months and is preferred in an early age to optimize testicular growth and protect fertility. The reason being the distance the testes must be relocated increases as the child grows. However, many young boys do not undergo this operation within the suggested guidelines. The reasons for this delay include a variety of factors, such as challenges within the family and a reliance on family caregivers for surgical referrals. Both race and insurance status were also identified as contributing factors. Delay in this operation can result in decreased fertility, increased necessity for assisted reproductive techniques, and an increased risk of developing testicular cancer later in life.
In the case of premature babies, surgeons use the corrected age to determine the best time to carry out this operation. If an undescended testis is left untreated for too long, it can lead to significant loss of germ cells and decreased fertility. Therefore, early surgery, known as orchidopexy, is usually recommended.
Many surgical techniques are available for this condition. For undescended testes that can be felt by touch, an inguinal or scrotal orchidopexy is recommended. If the testes cannot be felt by touch under anesthesia, exploratory laparoscopy is recommended. During this procedure, surgeons can choose between several procedures, depending on their findings. Whatever the chosen surgical approach, the surgeon’s training, experience, and preferences will play a major role in the decision-making process.
When the testis cannot be found during exploratory laparoscopy, it becomes important to rule out a missing testis by locating either blind-ending vessels or a testicular nubbin. If the internal ring is closed but vessels are observed entering it, a scrotal exploration is usually performed to look for a testicular nubbin. This is small structure that would confirm the presence of the undescended testis. If the internal ring is open, an inguinal or scrotal exploration may be needed if the testis cannot be pushed into the abdomen.
What else can Cryptorchidism (Undescended Testicle) be?
It can be tricky for doctors to tell the difference between a “retractile testicle” and a testicle that doesn’t naturally move down into the sac that holds the testicles (the scrotum). A retractile testicle is a lot more common than a testicle that doesn’t descend, and it isn’t something that requires surgery to fix. The retractile testicle is moved by the cremaster muscle, which makes the testicles pull up into the top part of the scrotum and into the canal that leads back into the body. This muscle reflex happens more in babies.
It can be tough for doctors to tell whether a retractile testicle that’s high up in the scrotum is different from one in the canal leading to the scrotum. Doctors might use different methods to find out, like asking the patient to cross their legs, using soapy fingers during the examination, or checking the patient while they’re in a warm bath.
According to the professional guidelines from the American Urological Association (AUA), a retractile testicle is one that is initially found outside the scrotum or can easily be moved out of the scrotum. This is usually because of the cremasteric reflex. However, with some effort, the testicle can be moved back down to its regular place in the scrotum without any discomfort or trouble.
What to expect with Cryptorchidism (Undescended Testicle)
If properly diagnosed and treated, cryptorchidism, which is a condition where one or both of the testes fail to descend, has an excellent prognosis or outcome. But there’s a slight increase in the risks of conditions like testicular cancer and infertility compared to those without the condition.
A study from Denmark involved over 6000 men showed that those who had a history of cryptorchidism had weaker functionality of the testes. They had a reduction of 3.5 mL in testis volume, a 28% decrease in sperm concentration, and lesser functioning of the Leydig cells, responsible for producing testosterone, compared to men who never had cryptorchidism.
Possible Complications When Diagnosed with Cryptorchidism (Undescended Testicle)
Orchiopexy, a surgical procedure to move an undescended testicle into the scrotum, can sometimes lead to serious complications. Two main complications are testicle shrinkage (atrophy) and testicle moving back upwards (testicular ascent). These occur around 1% of the time when the testicles can be felt (palpable testes). However, the rate of complications increases to around 5% for procedures done using a camera and tiny instruments (laparoscopic orchiopexies). The risk of testicle atrophy in an FS orchiopexy, which can be done in 1 or 2 stages, is much higher, between 20% to 30%. The outcomes can be worse if the procedure is done in one stage. Overdoing the handling and manipulation of the spermatic cord in orchiopexy can cause the loss of the testis, which is a severe complication.
Main Risks of Orchiopexy:
- Testicle shrinkage (atrophy)
- Testicle moving back upwards (testicular ascent)
- In 1% of the time for palpable testes
- 5% for laparoscopic orchiopexies
- Increased risk (20%-30%) of atrophy in FS orchiopexies
- Potential loss of the testis due to excessive handling of the spermatic cord
Preventing Cryptorchidism (Undescended Testicle)
Doctors need to make sure that a newborn boy’s testicles are in the right place. This is very important because the testicles might move into the right place on their own within the first 6 months of life. It is also very important for doctors and parents to regularly check the boy’s scrotum for any unusual signs or discomfort.
Doctors should make sure to tell both the patient and their families about the normal course of an undescended testicle condition, and they should highlight the importance of early surgery. The doctor should underline the importance of timely treatment and the risks that come with unnecessary surgical delays.