What causes hydrocele in adults

Key Takeaways

  • Hydrocele in adults occurs when excess fluid accumulates around the testicle because fluid production and absorption become imbalanced.
  • Ageing, inflammation, infection, injury, abdominal pressure, hernias and post-surgical changes are the most common causes.
  • Hydroceles usually grow slowly, but infections or trauma can cause faster, more noticeable swelling.
  • Most hydroceles are harmless, but large or painful ones may require treatment.
  • Surgery is the only permanent cure, while non-surgical methods offer temporary relief.

Introduction

Discovering a swelling in the scrotum can feel alarming. Many men immediately wonder whether it is dangerous, whether it is linked to an injury or infection or if it might go away on its own. These concerns are completely normal.

If you are noticing a soft, fluid-like swelling or heaviness around the testicle, understanding what causes hydrocele in adults can help you make sense of your symptoms and reduce unnecessary worry. This guide explains every major cause, how fast hydrocele can grow and when it’s time to see a doctor, so you feel confident and informed moving forward.

What Is Hydrocele in Adults?

A hydrocele is a fluid-filled swelling around the testicle that develops when the thin protective membrane (tunica vaginalis) holds more fluid than the body can absorb. The swelling is usually painless at first but may cause heaviness or discomfort as it grows. If you want to understand treatment options, surgery types or recovery details, you can explore our complete treatment guide here: Hydrocele Treatment in Bangalore

What Causes Hydrocele in Adults?

Hydrocele forms when there is a mismatch between fluid production and fluid absorption inside the scrotal sac. In adults, several factors can disrupt this balance. Let’s look at the most common causes seen in medical practice.

  1. Idiopathic Hydrocele

Many adult hydroceles have no identifiable cause. This is called idiopathic hydrocele. It develops quietly over months or even years. Men usually notice a soft swelling that grows slowly, but remains painless in the early stage. Idiopathic hydrocele is especially common in men over forty.

  1. Age-Related Tissue Changes

As men age, the tissues around the testicle gradually lose their ability to regulate fluid. This reduced efficiency means that even a small imbalance in daily fluid production can lead to accumulation. Older men often develop hydrocele for this reason alone, without any infection or trauma.

  1. Inflammation Inside the Scrotum

Inflammation in the epididymis, testicle or spermatic cord can cause hydrocele. Inflammation increases fluid production and reduces drainage at the same time, creating a dual effect. Many men experience this after minor irritation, strenuous physical activity or prolonged friction in the groin area.

  1. Hernia or Increased Abdominal Pressure

An inguinal hernia allows abdominal fluid to move down into the scrotum. Even without a hernia, conditions such as chronic coughing, constipation or heavy lifting increase abdominal pressure and disturb normal lymphatic flow. Over time, this pressure imbalance can lead to hydrocele formation.

  1. Post-Surgical or Medical Trauma

Hydrocele may appear after surgeries like hernia repair, varicocele treatment or testicular procedures. Temporary inflammation or disruption of lymphatic channels during healing can cause persistent fluid buildup. Some cases resolve on their own, while others become long-standing.

Quick Tip: Any painless but persistent swelling in the scrotum — especially if it increases in size over time — should be evaluated early. A timely consultation with a urologist at Medfine Hospital helps detect hernia-related or infection-related causes and ensures the safest treatment plan.

Why Does Hydrocele Happen?

Let’s look at what actually goes wrong inside the scrotum. Under normal conditions, the tunica vaginalis produces a small amount of lubricating fluid, and the body steadily reabsorbs it.

A hydrocele forms when this balance is disrupted. The body produces too much fluid, or the lymphatic system absorbs too little, or both. Inflammation, pressure, injury and ageing are the major reasons why this imbalance develops.

Can Hydrocele Develop Suddenly or Gradually?

Hydrocele most often develops gradually. Men usually describe a mild swelling that becomes more noticeable over weeks or months. This slow pattern is typical of idiopathic or age-related hydrocele.

However, hydrocele can also appear suddenly. Rapid swelling is often linked to infection or injury and may indicate inflammation or fluid leakage inside the scrotum. Any sudden or painful swelling should be checked promptly because it can hide more urgent conditions like torsion or hernia.

How Fast Does a Hydrocele Grow?

Growth speed varies widely among adults with hydrocele. Many hydroceles expand slowly over months, which is why men often feel the swelling “looks the same most days” until it gradually becomes more noticeable.

However, hydroceles related to inflammation, recent injury, or active infection may appear to enlarge more quickly. This is because irritation in the scrotal tissues can temporarily increase fluid production. Although this is not always rapid, it may progress faster than age-related hydroceles.

Doctors generally observe the pattern of swelling, associated symptoms, and history of trauma or infection to understand the likely cause—rather than relying on growth speed alone.

Can an Injury Cause Hydrocele?

The short answer is yes. Injury is a well-known trigger for hydrocele in adults. When the scrotum experiences a direct impact—during sports, accidents or falls—the tissues may inflame or sustain minor internal damage. This disrupts fluid drainage and leads to swelling.

Some men notice swelling within a few hours, while others see it develop gradually the next day. If swelling follows an injury, especially if there is pain, bruising or hardness, it is important to get checked to rule out other complications.

Can Infection Lead to Hydrocele?

In many cases, yes. Infection is one of the most common causes of hydrocele in adult men. Infections such as epididymitis, orchitis or urinary tract infections inflame the scrotal structures, causing fluid production to increase and drainage to slow down.

The NHS also recognises infections as a frequent cause of secondary hydrocele. Infection-related hydrocele may develop more quickly and feel warm or tender.

Types of Hydrocele in Adults

Understanding the type of hydrocele can help you know what to expect and how it might behave.

  1. Primary Hydrocele

Primary hydrocele is the most common type in older men. It develops slowly and without any specific underlying cause. Many men notice the swelling during routine activities or while bathing. Although it is usually painless, it may grow large over time and create discomfort or heaviness.

  1. Secondary Hydrocele

    Secondary hydrocele forms due to another condition such as infection, inflammation, tumour, injury or past surgery. The swelling may appear more quickly than primary hydrocele and can be associated with mild discomfort or warmth. The key is identifying and treating the underlying cause alongside the hydrocele.
  1. Communicating Hydrocele

A communicating hydrocele occurs when a channel between the abdomen and scrotum remains open. This allows abdominal fluid to move into the scrotal sac. Swelling may increase during standing or physical activity and reduce during rest. Although more common in childhood, adults can also develop this if the channel remains partially open.

  1. Encysted Hydrocele

Encysted hydrocele forms when fluid becomes trapped along the spermatic cord, not around the testicle itself. It often presents as a distinct, movable lump above the testicle and is commonly mistaken for hernia or cyst. While usually harmless, it may require treatment if it grows or becomes uncomfortable.

Is Hydrocele Dangerous?

Hydrocele is generally harmless, but not always completely risk-free. Large or rapidly growing hydroceles can cause discomfort or interfere with walking and exercise. They may also hide underlying issues such as hernias or infections.

If swelling becomes painful, warm, red or firm, it is better to seek medical care. These symptoms may indicate infection or other complications.

When Should You See a Doctor?

You should see a doctor if you notice any of the following:

• The swelling increases quickly

Fast growth can indicate infection, injury or hernia-related issues, and should be evaluated promptly.

• The swelling follows an injury

A hydrocele after trauma may hide internal bleeding or testicular damage, which need timely care.

• The scrotum feels painful, heavy or uncomfortable

While hydrocele is usually painless, new or increasing discomfort should be assessed.

• There is fever, warmth or redness

These signs point to infection, which can worsen if untreated.

• You feel a hard or unusual lump

Hydrocele is normally soft. A firm, uneven or unusual lump needs immediate examination.

• The swelling lasts longer than six months

Persistent hydrocele may need surgical correction, especially if it affects quality of life.

• The swelling becomes large enough to affect movement or daily activities

Large hydroceles can stretch the skin and limit comfort, making medical treatment advisable.

If any of these apply to you, you can consult our specialists directly

Can Hydrocele Be Treated Without Surgery?

In adults, hydrocele rarely goes away on its own. Medicines may reduce discomfort or treat infections but cannot remove the fluid once it has collected. Home remedies offer temporary relief, not a cure.

Permanent treatment requires surgical correction such as laser hydrocelectomy or open hydrocelectomy. These procedures safely restore normal fluid balance and prevent recurrence.

Is Hydrocele Surgery Painful?

Hydrocele surgery is generally not painful, because doctors use local or spinal anesthesia to numb the scrotal area completely before beginning the procedure. Most patients describe the experience as comfortable, with only a sensation of light pressure or movement rather than sharp pain. Once the anesthesia wears off, it is normal to feel mild soreness, heaviness, or tightness in the scrotum for a short period. This discomfort is usually manageable with simple medications and tends to improve quickly over the next few days.

Recovery is also easier than many expect. Most men are able to walk comfortably on the same day, resume work within 2–5 days, and return to full activity in about one to two weeks. Laser or minimally invasive techniques—where available—often make healing even faster with fewer stitches and less swelling. You can explore the full procedure details and recovery expectations here: Hydrocele Surgery Guide

Conclusion

Hydrocele in adults appears when something interferes with the body’s natural ability to manage fluid around the testicle. Ageing, infection, trauma, inflammation and abdominal pressure are common reasons. While usually harmless, hydrocele can grow large enough to cause discomfort or worry.

If you are experiencing swelling, remember that you are not alone. Many men face this condition, and most find relief with proper evaluation and treatment. Understanding what caused the hydrocele is the first step toward getting the right care and regaining comfort.

Related Links