The human body undergoes changes over time, but not all of them are expected. Changes in the anatomy, shape, and size of genitalia can be alarming, especially regarding the difference in size between testicles. Could this be a cause for concern?
The human body has some duplicate members, positioned on opposite sides of the body. Arms, hands, legs, feet… and also testicles. In this case, comparing the members is common, with an expectation that they should be equal in length, or at least, very similar.
However, this won’t always be the case. In other words, there is a normal (and even expected) variation among body members, such as testicles, which can indeed be of different sizes — this shouldn’t be harmful as long as the difference doesn’t exceed certain limits.
When noticing different testicle sizes, it’s important to assess the case carefully and avoid getting alarmed right away. Variations in size are normal, but they can also indicate more serious conditions like varicocele, tumors, or cancer in the region.
What can cause the difference in size between testicles?
Firstly, it’s important to emphasize that a common difference exists between testicles, and men can often expect to find one testicle larger than the other. It’s very common for the left testicle to be positioned lower than the right one. The difference in position in the testicular sac can even create an optical illusion that the sizes are different, but it’s just a matter of positioning.
During puberty, between approximately 12 and 21 years, boys undergo bodily changes influenced by hormones. The size of the penis and testicles changes significantly during this phase until it stabilizes in adulthood.
Among adult men, testicular size varies between 15 cm3 and 25 cm3, and the considered normal variation between the two testicles is up to 20%. When this difference is greater, or it accompanies pain and even changes in penile dimensions, it’s important to investigate what’s happening.
Here are the main causes for abnormal testicular volume:
Varicocele
The development of varicocele corresponds to the abnormal dilation of testicular veins. They are similar to varicose veins found in the legs — but in the testicles — and besides altering their size, they can also be a cause for male infertility.
Testicular Cancer
The formation of cancer or tumor in the testicular region results in the development of lumps or nodules in the testicle. This can cause a difference in size between the testicles and, in addition, provoke significant pain.
The initial symptom of testicular cancer is swelling of the organ, due to the abnormal multiplication of cells.
The disease may only manifest in more advanced stages, indicating a higher risk for men. Hence, self-examination and frequent visits to the urologist are fundamental. Diagnosing the disease early is often better for treatment outcomes.
American studies from Baylor College in Texas suggest that men with a curved penis are more likely to develop testicular cancer. Penile curvature can undergo changes due to diagnoses such as Peyronie’s Disease, responsible for altering the dimension, curve, and size of the penis and testicles.
Testicular Hydrocele
A hydrocele is the accumulation of fluids in the scrotal region, in the outer sac that contains the testicles. The main symptom is the sudden swelling of one or both testicles.
Hydrocele is more frequent among newborns — but can also affect adult men — albeit at rarer occasions.
Testicular Lump
A lump on the testicle is one of the main symptoms of different diseases in the male reproductive system. It doesn’t just indicate one testicle being larger than the other, but a change in the consistency and texture of the region, which should be worrying.
Finding a lump on the penis or testicles could indicate the presence of some STI (sexually transmitted infection), cancers, fibrosis and other diseases.
How to know if the testicles are normal?
To make sure that everything is okay or if there is need for a clinical intervention, men need to frequently visit the doctor and seek a reputable diagnosis of the situation.
Consult a Urologist
Men should visit the urologist regularly to ensure everything is okay, especially after 45 years of age, a phase marked by hormonal changes and changes in male health. The baseline recommendation is that men should visit their urologists at least once a year for routine exams. If any difference in testicle or penis size is identified, an appointment should be scheduled immediately. Only a specialist doctor will be able to investigate and provide an appropriate diagnosis.
Perform Self-Exams Regularly
Between one appointment and another, it is important for men to perform self-exams. Self-examination is an indicator of the health of the intimate region and could help identify any abnormalities in the testicles or penis. A man can perform a testicular self-exam preferably after a warm bath, with the scrotum more relaxed. Then, stand in front of the mirror and use both hands to examine and handle the testicles, looking for abnormalities in size, skin, or any sensation of pain when touching specific parts of the scrotum.
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