Varicocele is an enlargement of the veins inside the scrotum, usually caused by blood pooling in the pampiniform plexus rather than flowing efficiently back toward the heart. It is similar to a varicose vein in the leg, but it happens around the testicle. A varicocele is common, often develops during puberty, and matters because it can sometimes cause scrotal discomfort, testicular shrinkage, lower testosterone in some men, or problems with sperm quality and fertility.
Many men with a varicocele have no symptoms and never need treatment. But when a varicocele is large, painful, or linked with abnormal semen analysis results, testicular changes, or infertility, medical evaluation is worth pursuing.
Varicocele at a glance
- A varicocele is a collection of enlarged veins in the scrotum, most often on the left side.
- It may cause a dull ache, heaviness, visible enlarged veins, or no symptoms at all.
- Varicoceles are a common finding in men and are more common in men being evaluated for infertility.
- Not every varicocele harms fertility, but some are associated with lower sperm count, reduced motility, and abnormal sperm shape.
- Diagnosis is usually made by physical exam and sometimes confirmed with a scrotal ultrasound.
- Treatment is not always necessary; it depends on pain, fertility goals, semen results, and testicular health.
- Repair options include microsurgical varicocelectomy and embolization.
- If a varicocele appears suddenly, especially on the right side or later in life, prompt medical assessment is important.
What is a varicocele?
A varicocele is an abnormal enlargement of the veins that drain blood from the testicle. These veins are part of the pampiniform plexus, a network that helps regulate testicular temperature and supports normal testicular function.
In a varicocele, blood flow becomes less efficient, often because the vein valves do not work well or because of pressure differences in the venous drainage system. Blood can back up and the veins stretch out. Over time, this may create a “bag of worms” feeling on exam, especially when standing or bearing down.
Varicoceles most commonly occur on the left because the left testicular vein drains into the left renal vein at a less favorable angle and under different pressure conditions than the right side. Some men have bilateral varicoceles, and isolated right-sided varicocele is less common and may warrant closer evaluation depending on the clinical picture.
Alternate names and related phrases
- Scrotal varicose veins
- Enlarged testicular veins
- Pampiniform plexus dilation
- Varicocele in men
- Left-sided varicocele
Why varicocele matters for men’s health and fertility
A varicocele matters because the testicles work best at a temperature slightly lower than core body temperature. The pampiniform plexus helps with this cooling system. When these veins become enlarged and blood pools, the local environment may change in ways that can affect testicular function.
Potential consequences include:
- Reduced sperm quality, including lower sperm concentration, movement, or morphology
- Testicular discomfort, often described as a dull ache or heaviness
- Testicular atrophy, or a smaller testicle on the affected side
- Possible impact on testosterone production in some men
- Potential contribution to male infertility, especially when paired with abnormal semen analysis findings
It is also important to keep perspective: many men with a varicocele father children naturally and have no symptoms. A varicocele is a risk factor and a treatable contributor in some cases, not an automatic cause of infertility.
What causes a varicocele?
The exact mechanism is not always one single cause, but a varicocele generally develops because blood does not drain properly from the veins around the testicle. Contributing factors may include:
- Faulty or weak vein valves that allow backward blood flow
- Anatomy of the left testicular vein, which can create higher venous pressure
- Compression or pressure changes within abdominal or renal veins
- Pubertal growth, when increased blood flow to the testicles can make an underlying issue more noticeable
Why most varicoceles are on the left
The left testicular vein drains into the left renal vein, while the right testicular vein usually drains more directly into the inferior vena cava. This difference in anatomy is one reason left-sided varicoceles are much more common.
Can a varicocele be caused by exercise or masturbation?
No clear evidence shows that masturbation causes a varicocele. Heavy lifting or straining may make an existing varicocele more noticeable by increasing abdominal pressure, but these activities are not usually the root cause.
When secondary causes matter
Most varicoceles are primary and benign. However, a varicocele that appears suddenly, is new in an older adult, or is isolated to the right side may occasionally reflect another issue affecting venous drainage. That is why clinicians sometimes evaluate atypical cases more carefully.
Symptoms and signs of varicocele
Many varicoceles cause no symptoms. When symptoms do occur, they often develop gradually rather than suddenly.
Common symptoms
- Dull, aching, or dragging pain in the scrotum
- A feeling of heaviness or pressure
- Discomfort that worsens after standing for a long time or exercise
- Visible or palpable enlarged veins in the scrotum
- Symptoms that improve when lying down
Other possible findings
- One testicle, often the left, appears smaller
- A “bag of worms” sensation on self-exam or physical examination
- Infertility discovered during workup rather than obvious physical symptoms
Sharp severe pain is less typical. Sudden pain, marked swelling, fever, redness, trauma, nausea, or severe tenderness should not be assumed to be a varicocele and deserves prompt medical attention because conditions like testicular torsion, infection, or other urgent causes can present differently.
What’s normal vs what’s not?
It can be hard to know what is a normal scrotal finding and what needs evaluation. The table below offers a practical guide.
| Finding | Often less concerning | Reason to seek medical evaluation |
|---|---|---|
| Mild visible veins | More noticeable in warmth or after exertion | New enlargement, asymmetry, or associated pain |
| Scrotal discomfort | Occasional mild heaviness that settles with rest | Persistent pain, worsening symptoms, or impact on daily activity |
| Testicle size | Minor natural asymmetry can occur | Clear shrinkage of one testicle, especially in adolescents or young men |
| Side affected | Left-sided varicocele is common | Sudden right-sided or non-reducible varicocele |
| Fertility | Normal semen analysis despite varicocele | Difficulty conceiving, abnormal semen parameters, recurrent fertility concerns |
How a varicocele is diagnosed
Diagnosis usually starts with a medical history and physical exam. A clinician often examines the scrotum while you are standing and may ask you to perform a Valsalva maneuver (bearing down as if exhaling against a closed airway), which can make a varicocele easier to feel.
Common steps in diagnosis
- Symptom review — pain, heaviness, fertility concerns, duration, and whether symptoms change with position.
- Physical examination — assessing both sides of the scrotum, testicle size, tenderness, and whether veins are visible or palpable.
- Scrotal ultrasound — used when the physical exam is unclear, to confirm vein enlargement, or to assess blood flow and testicular size.
- Semen analysis — important when fertility is a concern.
- Hormone testing — sometimes ordered if testosterone issues, low libido, fatigue, or broader fertility concerns are present.
What ultrasound may show
A scrotal ultrasound can detect enlarged veins and reflux, meaning backward flow of blood. It also helps rule out some other causes of scrotal symptoms. Ultrasound is particularly useful for smaller or non-palpable varicoceles.
Palpable vs subclinical varicocele
- Palpable varicocele: can be felt on physical examination.
- Subclinical varicocele: seen on imaging but not felt on exam.
This distinction matters because treatment recommendations are often stronger when a varicocele is palpable and linked with symptoms or abnormal fertility findings.
Varicocele grades and severity
Clinicians often classify a varicocele by grade based on the physical exam.
| Grade | Description | What it usually means clinically |
|---|---|---|
| Subclinical | Seen on ultrasound but not felt on exam | May not need treatment unless there is a specific reason |
| Grade I | Small; felt only with Valsalva maneuver | Often mild; significance depends on symptoms and fertility findings |
| Grade II | Felt while standing without Valsalva | More clearly established on exam |
| Grade III | Large; visible through the scrotal skin | More likely to be associated with symptoms or testicular impact, though not always |
Severity on exam does not perfectly predict fertility impact. Some men with smaller varicoceles have abnormal semen parameters, while some with larger ones do not.
How varicocele can affect sperm and fertility
Varicocele is one of the most common treatable findings in men evaluated for infertility. The exact reasons it can affect fertility are still being studied, but several mechanisms are thought to contribute.
Possible ways a varicocele may impair sperm production
- Higher scrotal temperature, which can interfere with spermatogenesis
- Oxidative stress, which may damage sperm DNA or cell membranes
- Reduced oxygen delivery or altered blood flow within the testicle
- Hormonal changes affecting testicular function
- Accumulation of metabolic byproducts harmful to sperm production
Semen analysis findings that may be seen
- Lower sperm concentration or total sperm count
- Reduced sperm motility
- Abnormal sperm morphology
- In some cases, increased sperm DNA fragmentation
That said, a varicocele does not automatically mean infertility. Many men with a varicocele have normal semen parameters and normal fertility. Treatment decisions depend on the full picture, including test results, age, partner factors, duration of infertility, and goals for conception.
When varicocele repair may be considered for fertility
Repair may be considered when all or most of the following apply:
- A palpable varicocele is present
- The couple is trying to conceive
- There is abnormal semen analysis
- The female partner’s fertility status makes natural conception or treatment timing relevant
In adolescents, treatment may also be considered if the affected testicle is smaller or if there are signs of progressive testicular impact.
Varicocele and testosterone
The testicles produce both sperm and testosterone. Some evidence suggests that varicoceles may impair the function of Leydig cells, the cells involved in testosterone production, in a subset of men. This does not mean every man with a varicocele has low testosterone, but it can be part of the discussion if symptoms such as low libido, fatigue, reduced morning erections, or low energy are present.
Some men experience improved testosterone levels after varicocele repair, especially if levels were low beforehand, but outcomes vary. Hormone evaluation is individualized and may include total testosterone, free testosterone, LH, FSH, estradiol, and prolactin depending on the broader picture.
Treatment options for varicocele
Not every varicocele needs treatment. The main reasons treatment might be recommended are:
- Pain or scrotal discomfort that persists
- Infertility with abnormal semen analysis and a clinically significant varicocele
- Testicular atrophy or slower testicular growth in adolescents
- Selected hormone-related concerns in the right clinical setting
Conservative management
If symptoms are mild and fertility is not an immediate concern, clinicians may suggest observation and symptom management. This can include supportive underwear, limiting aggravating activities, and using pain relief if appropriate.
Surgical and procedural options
| Treatment | How it works | Potential advantages | Considerations |
|---|---|---|---|
| Microsurgical varicocelectomy | Small incision; enlarged veins are tied off under magnification while preserving arteries and lymphatics | Often considered the preferred surgical approach; lower recurrence and complication rates in experienced hands | Requires surgery and recovery time |
| Laparoscopic repair | Veins are clipped or sealed using laparoscopic instruments | Used in selected cases | General surgical risks; approach varies by surgeon and patient |
| Percutaneous embolization | An interventional radiologist blocks the affected vein using coils or sclerosants | No scrotal incision; may be useful in some recurrent or selected cases | Availability varies; not ideal for every anatomy or clinical situation |
What treatment can improve
- Scrotal pain in many men, though not all pain is due to varicocele
- Semen parameters in selected patients
- Natural conception chances in some infertile couples
- Testicular growth or symmetry in certain adolescent cases
- Testosterone levels in some men
What treatment does not guarantee
- Immediate fertility improvement
- Normal semen results in every case
- Pregnancy without considering female partner factors
- Complete relief if the pain has another cause
How long does improvement take?
If the goal is fertility, changes in semen parameters are not usually immediate. Sperm production cycles take time, so follow-up semen testing is often done several months after repair. A clinician may repeat testing at intervals based on the treatment plan and conception goals.
Risks and complications of repair
Complications depend on the procedure but may include recurrence, hydrocele formation, infection, bleeding, injury to nearby structures, or persistent pain. The risk profile tends to be most favorable with experienced operators and careful technique.
Self-care and lifestyle measures
Lifestyle changes cannot reliably “cure” a varicocele, because the underlying issue is venous anatomy and blood flow. Still, some measures may reduce discomfort or support overall reproductive health.
What may help
- Wear supportive briefs or an athletic supporter if heaviness or aching is bothersome
- Take breaks from prolonged standing when possible
- Notice whether heavy lifting worsens symptoms and modify accordingly
- Use over-the-counter pain relief only as appropriate and after checking with a clinician if needed
- Maintain a healthy weight and cardiometabolic health
- Limit tobacco exposure and excess heat to the scrotum
- Support fertility with sleep, nutrition, exercise, and reduction of excessive alcohol or anabolic steroid use
What to be cautious about
- Supplements marketed as “varicocele cures” are not a substitute for diagnosis or proper treatment
- Ice or heat should be used cautiously and not directly on the skin
- Do not ignore new or rapidly worsening scrotal symptoms
Questions to ask your doctor about a varicocele
- Is my varicocele palpable, subclinical, left-sided, right-sided, or bilateral?
- Do I need a scrotal ultrasound?
- Could this be contributing to pain, testicular size changes, or infertility?
- Should I get a semen analysis, and if so, how many tests are appropriate?
- Do I need hormone testing such as testosterone, FSH, or LH?
- Would observation be reasonable, or should I consider treatment now?
- Which repair option do you recommend in my case, and why?
- What are the chances this will improve pain or semen quality?
- How long after treatment should follow-up testing happen?
- Are there any signs that suggest another condition rather than a routine varicocele?
Common myths and misconceptions
“A varicocele always causes infertility.”
False. Many men with a varicocele have normal fertility. It is a possible contributor, not a certainty.
“If ultrasound shows a varicocele, it must be treated.”
False. Subclinical or incidental varicoceles do not always require intervention. Treatment depends on symptoms, fertility findings, and clinical context.
“A varicocele is dangerous.”
Usually false. Most are not dangerous. But atypical features such as sudden onset, isolated right-sided findings, or major swelling should be medically assessed.
“Pain means it’s severe.”
Not necessarily. Pain severity does not perfectly track with varicocele size, and not all scrotal pain comes from a varicocele.
“Surgery guarantees pregnancy.”
No. Treatment may improve semen parameters and fertility potential in selected cases, but conception depends on multiple factors, including partner fertility and timing.
When to see a doctor
Make an appointment if you notice a new scrotal lump, visible enlarged veins, persistent aching, one testicle appearing smaller, or fertility problems after trying to conceive. A non-urgent evaluation can help clarify whether a varicocele is present and whether it matters in your case.
Seek urgent care right away for:
- Sudden severe testicular or scrotal pain
- Rapid swelling
- Fever, redness, or severe tenderness
- Nausea or vomiting with acute scrotal pain
- Recent injury with major pain or swelling
These features can point to conditions that should not be delayed, especially testicular torsion.
Frequently asked questions
Can a varicocele go away on its own?
Usually not. A varicocele may feel less noticeable at times, especially when lying down, but the underlying vein enlargement generally does not fully resolve without a procedure.
Is varicocele a common cause of male infertility?
It is one of the most common treatable findings in men evaluated for infertility. Still, not every varicocele causes infertility, and not every fertility problem is due to a varicocele.
Can a varicocele cause low sperm count?
Yes, it can be associated with lower sperm count and other abnormal semen parameters. A semen analysis is the standard way to assess whether sperm production may be affected.
Does a varicocele lower testosterone?
It can in some men, but not all. If symptoms or history suggest hormone issues, a clinician may order blood tests to evaluate testosterone and related hormones.
Is surgery the only treatment for varicocele?
No. Observation may be appropriate when symptoms are minimal and fertility is not affected. When treatment is needed, options include surgery or embolization depending on the situation.
How painful is a varicocele?
Many men have no pain. When discomfort occurs, it is often a dull ache, heaviness, or dragging sensation rather than sharp severe pain.
Can exercise make a varicocele worse?
Exercise or heavy lifting can increase pressure and make symptoms more noticeable temporarily. They are not usually the main cause, but symptom patterns can help guide management.
Can you have a varicocele and still have children naturally?
Yes. Many men with a varicocele conceive naturally. Whether it affects fertility depends on semen quality, severity, duration, partner factors, and other aspects of reproductive health.
What side is a varicocele usually on?
Most often on the left side because of differences in venous anatomy. Bilateral varicoceles also occur. An isolated right-sided varicocele is less common and should be assessed in context.
What doctor treats a varicocele?
A urologist, especially one with experience in male reproductive medicine, commonly evaluates and treats varicocele. Interventional radiologists may perform embolization in selected cases.
References
- American Urological Association (AUA) and American Society for Reproductive Medicine (ASRM). Guideline on the diagnosis and treatment of infertility in men.
- European Association of Urology (EAU). EAU Guidelines on Sexual and Reproductive Health.
- Urology Care Foundation. Patient information on varicocele and male infertility.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Testicular and scrotal health resources.
- Johns Hopkins Medicine. Clinical overview of varicocele.
- Mayo Clinic. Varicocele overview and treatment information.
- Practice Committee documents and peer-reviewed reviews in reproductive urology and andrology literature addressing varicocele, semen parameters, and male infertility.
