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What is Varicocele?

Varicocele is an abnormal enlargement of the veins inside the scrotum, the pouch of skin that holds the testicles. It is similar to varicose veins of the legs and occurs when the veins of the pampiniform plexus become enlarged and twisted due to poor blood flow. Varicocele is one of the most common and treatable causes of male infertility. It can affect sperm production, sperm quality, and testosterone levels by increasing the temperature around the testicles.

Although many men with varicocele experience no symptoms, others may develop scrotal pain, heaviness, enlarged veins, or difficulty conceiving. Varicoceles are most commonly found on the left side of the scrotum because of differences in the anatomy of the testicular veins. Early diagnosis through physical examination and scrotal ultrasound can help determine the severity of the condition and guide appropriate treatment to improve fertility and relieve symptoms.

How Common is Varicocele?

Varicocele is one of the most common disorders affecting the male reproductive system and is frequently identified during infertility evaluations.

• Occurs in approximately 15% of all men.
• Present in about 35–40% of men with infertility.
• Most commonly affects men between 15 and 35 years of age.

Why Does Varicocele Occur?

Normally, veins in the scrotum contain one-way valves that allow blood to flow toward the heart. When these valves become weak or fail, blood flows backward (venous reflux), causing blood to collect inside the veins. Over time, the veins become enlarged, swollen, and twisted, resulting in a varicocele.

1. Failure of the venous valves.
2. Backward flow of blood (Venous reflux).
3. Blood pools inside the scrotal veins.
4. The veins enlarge and become twisted.

Why is Varicocele More Common on the Left Side?

Approximately 80–90% of varicoceles occur on the left side because of the unique anatomy of the left testicular vein.

• The left testicular vein is longer than the right.
• It drains into the left renal vein at a right angle.
• Pressure within the left renal vein is relatively higher.

Although uncommon, some men may also have:

• Right-sided varicocele
• Bilateral varicocele (affecting both testicles)

Types of Varicocele

1. Clinical Varicocele

A clinical varicocele can be detected during a physical examination because the enlarged veins can be felt by the healthcare provider.

2. Subclinical Varicocele

A subclinical varicocele cannot be felt during examination and is usually detected only with a scrotal ultrasound.

Grading of Varicocele

Grade 1

• Small varicocele.
• Detected only during the Valsalva maneuver (straining).

Grade 2

• Moderate-sized varicocele.
• Easily felt while standing without straining.

Grade 3

• Large varicocele.
• Visible through the scrotal skin.
• Often described as feeling like a "bag of worms."

Symptoms of Varicocele

Many men with varicocele do not experience symptoms. However, larger varicoceles may cause discomfort and affect fertility.

• Dull aching pain in the scrotum.
• Feeling of heaviness in the testicles.
• Visible enlarged veins in the scrotum.
• Pain that worsens after prolonged standing.
• Pain after physical exercise.
• Testicular shrinkage (Testicular atrophy).
• Difficulty conceiving (Male infertility).

How Does Varicocele Affect Fertility?

Varicocele increases the temperature around the testes, reducing the ability of the testicles to produce healthy sperm. It may also increase oxidative stress and impair testosterone production, leading to reduced fertility.

Varicocele may contribute to the following semen abnormalities:

• Low sperm count (Oligospermia)
• Poor sperm motility (Asthenozoospermia)
• Abnormal sperm morphology (Teratozoospermia)
• Complete absence of sperm (Azoospermia) in severe cases

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