Varicocele: Causes, Symptoms, Diagnosis and Treatment — Overview, Diagnosis & Treatment Options | MyMedicPlus

A varicocele is an abnormal enlargement and tortuosity of the veins of the pampiniform plexus within the spermatic cord, analogous to varicose veins in the lower extremities. It affects approximately 15% of all adult men and 40% of men presenting with infertility, making it the most common surgically correctable cause of male subfertility. Varicoceles occur predominantly on the left side (90%) due to the perpendicular drainage of the left testicular vein into the left renal vein, creating higher hydrostatic pressure; bilateral varicoceles are found in 30-40% of cases. Subclinical varicoceles are detected only by ultrasound Doppler, while grades I-III are palpable (grade I: palpable only with Valsalva; grade II: palpable without Valsalva; grade III: visible through the scrotal skin). The pathophysiological mechanisms include elevated scrotal temperature impairing spermatogenesis, reflux of toxic adrenal metabolites via the spermatic vein, and oxidative stress-mediated testicular damage.

Varicoceles develop primarily due to incompetent or absent valves within the internal spermatic vein, allowing retrograde blood flow and venous pooling in the pampiniform plexus. The anatomical predilection for left-sided varicocele is explained by the perpendicular angle at which the left testicular vein drains into the left renal vein (versus the oblique angle on the right side draining into the inferior vena cava), creating higher hydrostatic resistance. Prolonged standing and physical exertion that increases intra-abdominal pressure exacerbates venous pooling. A sudden-onset varicocele in an older man — particularly right-sided or when associated with haematuria — may indicate obstruction of the renal vein or inferior vena cava by a retroperitoneal mass (including renal cell carcinoma nutcracker syndrome) and requires abdominal imaging. There is no established genetic or dietary cause.

Most varicoceles are asymptomatic and discovered incidentally during infertility evaluation, sports physical examination, or scrotal self-examination. When symptomatic, patients report a dull, aching, or heavy scrotal discomfort that typically worsens with prolonged standing, physical exertion, or warm environments (all of which increase venous pooling), and improves with supine positioning or scrotal support. A palpable scrotal mass with the classic description of a 'bag of worms' superior to the testis is characteristic of grade II-III varicocele. Examination performed in the standing position with Valsalva maneuver is essential to detect grade I lesions. Testicular hypotrophy (reduced volume of the ipsilateral testis compared to the contralateral side) indicates ongoing spermatogenic damage and is an important indication for treatment in adolescents. Bilateral varicocele may cause bilateral testicular atrophy.

Clinical examination in the standing position with Valsalva maneuver is the primary diagnostic method and sufficient for grade II-III varicoceles. Scrotal colour Doppler ultrasound confirms the diagnosis, measures pampiniform plexus vein diameter (>3 mm is abnormal), and demonstrates retrograde venous flow during Valsalva — the hallmark of varicocele. Ultrasound also accurately measures testicular volume bilaterally and identifies subclinical varicoceles. Semen analysis (WHO 2021 reference values) is mandatory in men with infertility concern: oligozoospermia (sperm count <16 million/mL), asthenozoospermia (motility <42%), or teratozoospermia (normal morphology <4% by Kruger strict criteria) support treatment indication. Hormonal evaluation — serum FSH, LH, testosterone — identifies concurrent hypogonadism. Retroperitoneal CT or ultrasound is indicated for sudden-onset varicocele in men over 40 or right-sided predominant varicocele to exclude secondary causes.

Observation is appropriate for subclinical varicoceles, asymptomatic men not concerned about fertility, or adolescents without testicular growth arrest. Treatment is indicated for clinical varicocele with abnormal semen parameters and infertility, or symptomatic pain. Microsurgical varicocelectomy (subinguinal or inguinal approach with 15-25x optical magnification) is the preferred surgical technique, achieving the lowest recurrence rate (<1-2%) and fewest complications (post-operative hydrocele <1%, testicular artery injury <0.5%). Laparoscopic varicocelectomy offers similar efficacy with faster recovery but general anaesthesia requirement. Percutaneous retrograde embolization — radiologically guided sclerotherapy of the internal spermatic vein — is equally effective for pain relief and is preferred for surgical recurrence; recurrence rates of 10-15% are higher than microsurgery. Antioxidant supplementation (vitamin C, E, coenzyme Q10, L-carnitine) may improve semen parameters as adjunctive therapy. In men with non-obstructive azoospermia and varicocele, microsurgical varicocelectomy can restore sperm to the ejaculate in 20-40% of cases, enabling IVF/ICSI.

The prognosis following varicocele treatment is generally favorable across all three major indications — pain, fertility, and adolescent testicular growth. For pain relief, varicocelectomy or percutaneous embolization achieves clinically significant reduction in scrotal discomfort in approximately 70–90% of symptomatic patients, with microsurgical varicocelectomy providing the highest success rates and lowest recurrence. For fertility outcomes, semen analysis improvements — increased sperm concentration, progressive motility, and morphology — are observed in approximately 60–70% of men within 3–6 months after successful repair. Natural pregnancy rates within 12 months of microsurgical varicocelectomy are approximately 30–40% in couples where female fertility evaluation is normal; the natural pregnancy rate without treatment in similar couples is approximately 15–20%. The overall pregnancy benefit of varicocelectomy in clinical varicocele with abnormal semen parameters was confirmed in a meta-analysis of randomized trials and in a Cochrane systematic review showing benefit over observation. Recurrence rates after microsurgery are 1–2%, compared to 10–15% for open surgery and slightly higher for radiological embolization; microsurgical subinguinal varicocelectomy offers the lowest recurrence and complication rates. For adolescents with clinically significant varicocele and progressive testicular volume loss, early surgical repair typically results in catch-up growth of the affected testis within 12–18 months, potentially preventing permanent fertility damage. Non-obstructive azoospermia due to varicocele is reversible in approximately 20–40% of cases after varicocelectomy — sperm appears in the ejaculate where none was previously found — avoiding the need for surgical sperm retrieval for IVF in a meaningful proportion of these patients. Long-term testicular function monitoring is recommended after repair.

Varicocele cannot be reliably prevented, as the underlying cause (incompetent venous valves) is largely anatomical and congenital. Avoiding prolonged periods of standing, wearing supportive scrotal underwear during physical activity, and maintaining a healthy body weight may reduce symptom severity by minimizing venous pooling. Regular testicular self-examination from adolescence allows early detection; any scrotal swelling or asymmetry should be evaluated. Adolescent males with varicocele detected at routine physical examination benefit from periodic monitoring of testicular volume — progressive ipsilateral testicular hypotrophy (>20% volume difference) is an indication for varicocelectomy to prevent permanent fertility impairment. Early treatment during adolescence, when the testes are still developing, may offer greater spermatogenic recovery potential than treatment in adulthood.

Men experiencing scrotal discomfort — particularly a dragging or heavy ache that worsens with standing or physical activity — should consult a urologist. Any palpable scrotal swelling above the testis, or a scrotal mass with a 'bag of worms' texture, warrants evaluation. Men (or couples) who have been trying to conceive without success for 12 months (or 6 months if the female partner is over 35) should pursue a fertility evaluation including male semen analysis, which may reveal varicocele as a contributory factor. Adolescents with a palpable varicocele and a smaller ipsilateral testis (>20% volume difference) need urological follow-up to monitor for progressive testicular damage. A sudden-onset varicocele in a man over 40, especially right-sided, requires urgent abdominal imaging to exclude a retroperitoneal or renal mass causing venous obstruction.