Causes of Testicular Atrophy in Men

Noticing that one or both testicles look smaller can be scary. Many men immediately worry about fertility, “mardana kamzori,” or long-term health problems. The truth is that testicular size can change for different reasons. Sometimes the change is temporary and improves with treatment. Other times it is a warning sign that needs urgent medical attention.

Testicular atrophy simply means the testicle has become smaller and may also be producing less testosterone or fewer sperm than before. It can happen in one testicle or both. In this article, you’ll learn the most common causes, the symptoms to watch for, when to treat it as an emergency, and what doctors usually do to diagnose and manage it especially in the context of men’s health care in Pakistan.

What Is Testicular Atrophy (In Simple Words)?

Testicular atrophy means shrinkage of the testicles. A testicle can become smaller because the tissue inside it is not working properly, or because it has been damaged. It is important to understand that “smaller size” and “reduced function” often happen together. A testicle may shrink and also produce less sperm or testosterone. In some men, the testicle becomes softer. In others, it feels firmer or irregular depending on the cause.

A slight difference in size between the two testicles can be normal. Many men naturally have one testicle that hangs lower or looks slightly larger. The concern starts when you notice a clear change compared to your usual size, when the difference becomes obvious over time, or when shrinkage comes with pain, swelling, fever, or sexual or fertility issues.

Is Testicular Atrophy Serious?

Testicular atrophy is not always dangerous, but it should not be ignored. It can be serious because it may indicate a condition that affects blood flow, hormones, infection, or fertility. Some causes are reversible if caught early. Others can lead to permanent changes if treatment is delayed.

It matters for two main reasons. First, the testicles are responsible for sperm production, so shrinkage can affect fertility. Second, they produce testosterone, which supports energy, mood, libido, erections, muscle strength, and overall male health. If testicular function drops, symptoms may show up slowly and many men don’t connect them to testicular changes.

Common Symptoms Men Notice

The most common sign is that one testicle looks smaller than before, or the scrotum feels different. Some men notice a change while bathing, while others notice it because of discomfort or heaviness.

Other symptoms depend on the cause. You may feel a dull ache, especially after standing for long hours. Some men feel swelling, tenderness, or warmth. A “dragging” sensation can happen when veins are enlarged. If hormones are affected, you might notice low sex drive, fatigue, mood changes, or difficulty maintaining erections. If fertility is affected, the biggest sign is difficulty achieving pregnancy despite regular unprotected intercourse.

Causes of Testicular Atrophy in Men

Testicular atrophy can happen due to hormonal problems, blood flow issues, infections, trauma, childhood conditions, or chronic illness. Often, more than one factor is involved. Understanding the causes helps you understand what to do next.

Hormonal Causes

Hormones control sperm production and testicular health. When the hormonal signals are disrupted, the testicles may shrink and reduce their function.

One of the most common modern causes is the use of anabolic steroids or external testosterone. When a man uses steroids or testosterone injections without medical need, the body senses that testosterone is high. In response, the brain reduces the signals that normally tell the testicles to produce testosterone and sperm. Over time, the testicles become less active and can shrink. This is why many men who use bodybuilding steroids notice smaller testicles and sometimes reduced fertility.

Even medically supervised testosterone replacement therapy can cause shrinkage in some men, because it still reduces natural production signals. This does not mean TRT is always “bad,” but it must be managed carefully especially for men who want children.

Other hormonal problems include pituitary gland disorders. The pituitary gland in the brain controls reproductive hormones. If it is not working properly, testosterone may drop and the testicles can reduce function. Thyroid problems can also indirectly affect reproductive hormones and sperm health.

Aging can contribute as well. Testosterone tends to decline gradually with age. In many men, this is mild and does not cause noticeable shrinkage. But in some men, hormonal decline combined with chronic illness, stress, poor sleep, or obesity can contribute to reduced testicular function.

Blood Flow Problems and Vascular Causes

Healthy blood flow is essential for testicular tissue. If the blood supply is reduced or the veins are not draining properly, the testicle can become damaged and shrink.

Varicocele is one of the most common causes linked to fertility. It happens when the veins in the scrotum become enlarged, similar to varicose veins in the legs. This can raise the temperature around the testicle and disturb normal circulation. Over time, it may affect sperm production and can contribute to a smaller testicle, particularly on the left side. Some men feel heaviness, dull pain, or a “bag of worms” texture in the scrotum.

Testicular torsion is a much more urgent condition. It happens when the spermatic cord twists and cuts off blood supply to the testicle. This is a medical emergency. Severe sudden pain is the classic sign, often with swelling and nausea. If blood flow is not restored quickly, the testicle can be permanently damaged and may shrink or even be lost. Torsion is more common in teenagers and young men, but it can happen at any age.

Infections and Inflammation

Infections can inflame the testicle and damage the delicate tissue that makes sperm.

Orchitis means inflammation of the testicle. It can be caused by viruses or bacteria. Mumps orchitis is a well-known cause. When mumps occurs after puberty, it can affect the testicles and sometimes leads to shrinkage and fertility problems. This is one reason vaccination matters.

Bacterial infections can also cause orchitis, especially if infection spreads from the urinary tract or prostate. Sexually transmitted infections may be involved in some cases. If you have testicular pain with fever, burning urine, discharge, or swelling, it is important to seek medical evaluation instead of self-medicating.

Some infections resolve without long-term damage, but severe or untreated infections can lead to scarring and atrophy over time.

Trauma and Physical Stress

Direct injury to the testicles can damage tissue and reduce function. Trauma may happen during sports, accidents, or physical work. Sometimes, swelling occurs first, then shrinkage develops later due to internal damage.

Surgery in the groin or scrotal area can also affect the testicle if blood supply is compromised. Chronic pressure and long-standing swelling from conditions like large hydrocele can sometimes contribute to discomfort and reduced function, especially if ignored for a long time.

Undescended Testicle (Cryptorchidism)

Some boys are born with one or both testicles not descending into the scrotum. If this condition is not corrected early in childhood, the testicle may not develop normally. It can lead to smaller size and reduced sperm production later in life. It also increases the risk of other problems, so men with a history of undescended testicle should be extra careful with follow-up.

Chronic Illness and Systemic Causes

Some long-term diseases affect hormones and testicular function indirectly. Severe liver disease can change hormone balance. Certain cancers and treatments like chemotherapy can damage sperm-producing cells. Long-term uncontrolled diabetes and severe obesity can also reduce testosterone levels and affect sperm health.

Some men report changes in reproductive health after significant viral illness, and inflammation may play a role. The key point is that if testicular shrinkage happens along with major changes in health, it should be discussed with a doctor as part of a full evaluation.

What’s Happening Inside the Testicle?

Inside the testicles are tiny tubes called seminiferous tubules. This is where sperm is produced. When the testicle is exposed to heat, poor blood flow, infection, inflammation, toxins, or hormonal disruption, these sperm-making structures can be damaged. Over time, healthy tissue may reduce and be replaced by less active tissue, leading to smaller size and lower function.

This is also why timing matters. If the cause is treated early, tissue may recover better. If damage continues for months or years, changes can become long-lasting.

When to Seek Urgent Help (Don’t Ignore These Signs)

Not every case is an emergency, but some symptoms should be treated urgently.

Sudden severe testicular pain is the biggest red flag. This could be torsion, and delaying care can risk permanent damage. Pain with fever, swelling, and urinary symptoms may indicate infection that needs medical treatment quickly. A hard lump, rapid swelling, or unexplained scrotal changes should also be evaluated promptly to rule out serious conditions.

If you are unsure, it is safer to get checked rather than wait.

Diagnosis: How Doctors Find the Real Cause

Doctors usually start with a detailed history. They ask about timing, pain, fever, injuries, surgeries, sexual history, fertility attempts, steroid or testosterone use, and general health.

A physical exam helps identify swelling, tenderness, enlarged veins, or other changes. Scrotal ultrasound is one of the most important tests because it can assess blood flow and detect varicocele, torsion-related changes, swelling, and other structural issues.

Blood tests may be recommended to check testosterone and other reproductive hormones, especially if low libido, fatigue, or sexual dysfunction is present. If fertility is a concern, a semen analysis is often advised. In some cases, additional tests are done based on the suspected cause.

Can Testicular Atrophy Be Reversed?

Reversal depends on the cause and how quickly it is treated. Some men improve significantly when the underlying cause is corrected. For example, treating infections early, managing hormones properly, or addressing varicocele may improve testicular health and fertility outcomes.

However, if a testicle has lost blood supply for too long, or if damage has been severe and long-standing, full recovery may not be possible. Even in those cases, treatment can still help protect remaining function, reduce symptoms, and improve quality of life.

It’s also important to remember that sperm production follows a cycle. Improvements in sperm health often take two to three months to show after treatment or lifestyle changes.

Treatment Options Based on Cause

Treatment is not one-size-fits-all. It depends on what is causing the shrinkage.

Varicocele management may include monitoring, lifestyle advice, and in selected cases a procedure or surgery, especially when fertility is affected or the testicle is shrinking.

Torsion requires emergency surgical treatment to restore blood flow and prevent permanent damage.

Infections and orchitis are treated based on the cause. Bacterial infections usually need antibiotics. Viral causes are managed with supportive care and follow-up, and pain and swelling are treated appropriately.

Hormonal issues require careful evaluation. If steroids or non-prescribed testosterone are involved, stopping them without medical guidance is not always safe. Many men need a supervised plan, especially if fertility is a goal. In men on TRT who want children, doctors may discuss fertility-preserving options.

If fertility is affected, treatment may include a plan to improve sperm quality, manage lifestyle factors, treat varicocele, correct infections, and support reproductive health. Some couples may also consider assisted options if needed, depending on both partners’ evaluations.

Practical Prevention Tips (Pakistan-Relevant)

The best prevention is early awareness. Avoid non-prescribed steroids or testosterone. Get infections treated early and don’t ignore symptoms. Protect the testicles from injury during sports and physical work. Avoid prolonged heat exposure and tight clothing if you’re already facing fertility issues.

If you had mumps in adulthood or you were not vaccinated, and you notice testicular pain or swelling, seek medical advice. If you notice changes in size, pain, heaviness, or fertility issues, don’t delay evaluation.

How Dr. Farooq Nasim Bhatti Treatment Works?

If you are noticing testicular shrinkage, scrotal pain, fertility issues, or symptoms of low testosterone, professional evaluation can help you understand the real cause and the right treatment path. At Nasim Fertility Center Pakistan, men receive confidential, respectful care for male fertility and sexual health concerns. Dr. Farooq Nasim Bhatti and the team provide evidence-based assessment for sperm health, hormone imbalance, varicocele-related issues, and related male reproductive problems, with guidance tailored to your symptoms and goals.

Summary

Testicular atrophy can happen due to hormonal imbalance, steroid or testosterone use, varicocele, torsion, infections like orchitis, trauma, undescended testicle, and chronic illness. Some causes are treatable and may improve with early care. Others can cause long-term changes if ignored. The most important step is not to panic, but also not to delay. If you notice a clear size change, persistent discomfort, fertility problems, or especially sudden severe pain, medical evaluation is the safest and smartest next step.

FAQs

What are five common causes of testicular atrophy?

Common causes include hormonal imbalance, steroid or testosterone use, varicocele, testicular torsion, and infections such as orchitis.

Is testicular atrophy harmful?

It can be harmful if it affects fertility, testosterone, or if it is caused by a serious issue like torsion or infection. Early evaluation is important.

Can testicular atrophy be reversed?

Sometimes, yes. If the cause is treated early—like infection, hormone issues, or varicocele—improvement is possible. Long-standing damage may be permanent.

How is testicular atrophy diagnosed?

Doctors usually diagnose it through history, physical examination, scrotal ultrasound, and sometimes hormone tests and semen analysis.

When does testicular atrophy start?

It can start at any age depending on the cause. Torsion and infections can cause sudden changes, while varicocele or hormones may cause gradual shrinkage.

Can steroids cause testicle shrinkage?

Yes. Steroids and external testosterone can reduce the body’s natural hormone signals, leading to testicular shrinkage and reduced sperm production.

Can varicocele shrink a testicle?

Yes. Varicocele can raise temperature and disrupt circulation, which may affect sperm health and can contribute to shrinkage over time.

Should I worry if one testicle is smaller than the other?

A small difference can be normal, but a sudden change, noticeable shrinkage, pain, or fertility issues should be evaluated by a doctor.

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