Bilateral Varicocele: Causes, Symptoms, and Treatments

A bilateral varicocele is an enlargement of the veins inside the scrotum on both sides, not just one. Most people assume varicoceles are overwhelmingly a left-sided problem, but imaging studies consistently show that the condition affects both sides far more often than physical exams alone suggest. When both sides are involved, the effects on sperm quality and testosterone production tend to be more pronounced, and the treatment approach shifts accordingly.

More Common Than Most People Realize

Textbooks have long taught that varicoceles are predominantly left-sided, occurring on the left in roughly 80 to 90 percent of clinically detected cases. That framing has stuck in popular understanding, but it reflects a limitation of physical examination rather than the true anatomy. When researchers use sensitive imaging to look at both sides carefully, bilateral involvement turns out to be the norm, not the exception.

In one study of 286 men with confirmed varicoceles, venography revealed that about 81 percent had bilateral disease, while only around 18 percent had a purely left-sided varicocele and fewer than 2 percent had a right-only varicocele.¹ A separate study using ultrasound found a similar pattern: roughly 78 percent of men had bilateral varicoceles confirmed on imaging, even when only one side had been detected on physical exam.² The gap between what the hand feels and what the ultrasound shows is large enough to matter clinically, because an undetected right-sided varicocele can undermine the benefit of repairing only the left.

What Causes Varicoceles on Both Sides

A varicocele forms when the valves inside the veins that drain blood away from the testicle stop working properly. Blood pools and the veins dilate, creating the characteristic “bag of worms” feel during a physical exam.³ On the left side, this happens more readily because of the way the left gonadal vein empties into the left renal vein at a steep angle, creating higher pressure. But the right side is not immune. The same valve incompetence can develop on the right, and when both sides are affected, the pooling of warm, poorly oxygenated blood surrounds both testicles.

Several factors can push someone toward developing varicoceles bilaterally. Chronic or repeated physical strain that raises intra-abdominal pressure is one recognized contributor.⁴ Taller body height, lower body mass index, and prolonged standing have also been flagged in epidemiologic research, though the evidence for each individual factor varies in strength.

In some cases, a bilateral varicocele is a clue to an underlying vascular compression problem. Nutcracker syndrome, where the left renal vein gets squeezed between the aorta and the superior mesenteric artery, raises venous pressure and can promote varicocele formation.⁵ Rare anatomical variants like duplicated renal veins can create a more complex version of this compression, with extensive pelvic varices and bilateral varicoceles as a result.⁶ A new right-sided varicocele appearing suddenly in an older man also warrants further workup, because it can occasionally signal a mass in the abdomen or kidney area pressing on the venous drainage.

How Bilateral Varicocele Affects Fertility

The core problem with any varicocele is heat. Pooled venous blood raises scrotal temperature, and sperm production is exquisitely sensitive to even small temperature increases. When both sides are involved, neither testicle gets the cooler environment it needs, and the damage to sperm tends to be more severe than when only one side is affected.

The harm goes deeper than just heat. Varicoceles trigger a cascade of oxidative stress inside the testicle. Reactive oxygen species overwhelm the sperm’s natural defenses, leading to DNA strand breaks in the sperm’s genetic material.⁷ This kind of DNA fragmentation is commonly found in the ejaculates of men with varicoceles and fertility problems, and it can affect not just the ability to conceive naturally but also outcomes with assisted reproduction. Emerging research suggests the damage extends to epigenetic regulation as well, with abnormal patterns of small RNA expression in sperm from men with varicoceles.⁸

Bilateral disease also hits testosterone production harder. In men with varicoceles on both sides, the Leydig cells (the cells in the testicle responsible for making testosterone) show lower density and reduced function compared with men who have a unilateral varicocele. Testosterone levels in the blood and the testicle’s own ability to synthesize testosterone are both significantly lower.⁹ This matters beyond fertility. Men with bilateral grade III varicoceles have been found to have significantly lower serum testosterone alongside elevated levels of the pituitary hormones FSH and LH, a pattern that indicates the testicles are struggling despite the brain sending stronger signals to produce more.¹⁰ In some men, this translates into symptoms like low energy, reduced sex drive, and erectile difficulties.

Getting the Diagnosis Right

A standard physical exam with the patient standing and performing a Valsalva maneuver (bearing down as if straining) can detect many varicoceles, but it misses a substantial number on the right side, as the data on bilateral prevalence makes clear. That is why color Doppler ultrasound has become the go-to tool for a thorough evaluation.

During a Doppler study, the technician measures the diameter of the largest vein in the pampiniform plexus on each side, both at rest and during a Valsalva maneuver. Vein diameters above about 2.5 mm at rest or about 3 mm during Valsalva predict a clinically significant varicocele with good accuracy.¹¹ The ultrasound also confirms retrograde blood flow, which is the hallmark of valve incompetence. One finding from Doppler research worth noting: when identical varicocele grades are compared between left and right sides, the vein diameters and flow patterns are similar, meaning a right-sided varicocele of the same grade is just as physiologically significant as a left-sided one.¹¹

For men being evaluated for infertility, a semen analysis is standard alongside imaging. And if there is any suspicion of a secondary cause, such as sudden onset in an older patient or an isolated right-sided varicocele, abdominal imaging may be warranted to rule out retroperitoneal masses or vascular compression syndromes.

Why Fixing Both Sides Matters

This is one of the most consequential findings in the varicocele literature, and it is worth understanding clearly: when bilateral disease is present, repairing only the left side leaves significant fertility impairment on the table. Even a small, subclinical varicocele on the right keeps dragging down sperm quality and testicular function if left alone.

A prospective randomized trial compared bilateral versus unilateral repair in men who had a clinical left varicocele alongside a subclinical right varicocele. A year after surgery, both groups showed improvement, but the bilateral group had significantly greater gains in sperm concentration, normal sperm shape, and progressive motility.¹² Another study put it more bluntly: even a small, unrepaired palpable right varicocele continues to harm bilateral testicular function, and men with bilateral palpable varicoceles require bilateral repair.¹³

A systematic review and meta-analysis pooling the available evidence confirmed this pattern across multiple studies. Spontaneous pregnancy rates were roughly 89 percent higher in couples where the man had bilateral repair compared with unilateral repair alone. Sperm concentration, motility, and morphology all showed greater improvements after bilateral surgery.¹⁴ In one subset analysis of men with low sperm counts, natural pregnancy rates reached 48 percent after bilateral microsurgical repair, compared with 15 percent after unilateral repair.¹⁵

Treatment Options

There are two broad approaches to treating bilateral varicocele: surgical repair and percutaneous embolization. Both aim to block the reflux of blood through the incompetent veins, redirecting flow through healthier venous pathways.

Surgical Repair

Microsurgical subinguinal varicocelectomy is widely considered the gold standard. The surgeon uses an operating microscope to identify and ligate the dilated veins while carefully preserving the testicular artery and lymphatic channels. This precision matters for reducing complications. In adolescent studies, microsurgical repair achieved a 0 percent recurrence rate and 0 percent hydrocele rate, compared with nearly 9 percent recurrence and 6 percent hydrocele when no magnification was used.¹⁶ A meta-analysis comparing laparoscopic with microsurgical approaches found that laparoscopic repair carried roughly a threefold higher risk of hydrocele and a sevenfold higher recurrence rate.¹⁷

For bilateral surgery, both sides are typically addressed during the same operative session through separate small incisions. One study of 109 bilateral microsurgical repairs reported significant improvement in both low motility and low count, with no severe complications.¹⁸ After bilateral repair, improvements in sperm motility, sexual function, and testosterone levels have been tracked over follow-up periods as long as three years, with partner pregnancy rates around 37 percent and improvements in sexual activity reported by 50 to 75 percent of patients.¹⁹

Percutaneous Embolization

Embolization is a catheter-based procedure performed by an interventional radiologist. A thin catheter is threaded through a vein, usually in the neck or groin, and guided into the gonadal veins, where coils, sclerosing agents, or other embolic materials are deployed to block the faulty vessels. It does not require general anesthesia and recovery is typically faster than with surgery.

A fifteen-year retrospective analysis found that embolization is safe, effective, and durable, with high technical success and low recurrence regardless of which embolic material was used. The study also noted that embolization works even in patients who have already had a failed surgical repair.²⁰ However, bilateral embolization does have a specific technical challenge: accessing the right gonadal vein can be harder than the left due to its anatomy. In one series, about 19 percent of right-sided embolization attempts failed to achieve complete obliteration, compared with only about 2 percent on the left.²¹ If the right side cannot be successfully embolized, a surgical repair on that side may be needed as a follow-up.

Complications and Recurrence

No treatment is risk-free. The most common complication of varicocelectomy is hydrocele, a fluid collection around the testicle. After bilateral repair, hydroceles may be more likely to grow large enough to require a second procedure to drain them. In one long-term follow-up, patients who developed hydroceles after bilateral varicocelectomy were significantly more likely to need hydrocelectomy than those who developed hydroceles after unilateral repair.²² Using microsurgical technique dramatically lowers this risk, because the surgeon can identify and spare the lymphatic channels whose disruption causes fluid to accumulate.

Recurrence is the other concern. A varicocele can come back months or even years after repair. In the same long-term follow-up, late recurrences appeared as far out as 76 months after surgery in patients who had been varicocele-free on earlier examinations.²² The practical takeaway is that follow-up should not stop after a single clean postoperative visit. A check at six to twelve months is standard, and some practitioners recommend periodic ultrasound surveillance for a few years, particularly in younger patients or those trying to conceive.

Testosterone Recovery After Repair

For men whose bilateral varicoceles have contributed to low testosterone, repair can produce a meaningful hormonal rebound. A meta-analysis of studies on testosterone changes after varicocelectomy found that mean serum testosterone levels increased by about 97 ng/dL after surgical repair.²³ That is not a trivial bump. For a man starting with borderline-low levels, it can be the difference between symptomatic testosterone deficiency and a level that supports normal energy, libido, and muscle maintenance.

Literature reviews have consistently supported this finding, concluding that varicocele repair can raise serum testosterone in men with varicoceles and testosterone deficiency.²⁴ Data specifically looking at bilateral surgical intervention have shown testosterone level recovery afterward.²⁵ This is worth emphasizing because it means varicocele repair can serve a dual purpose: improving fertility and addressing hormonal symptoms simultaneously, potentially reducing or avoiding the need for testosterone replacement therapy, which itself impairs sperm production.

Varicoceles in Adolescents

Varicoceles typically first appear during puberty, and they are the most common surgically treatable cause of male infertility. In adults, repair improves semen quality in roughly 60 to 80 percent of men and raises the likelihood of conception in up to 60 percent. But the decision-making in adolescents is murkier, because you are trying to prevent future harm rather than treat a current fertility problem, and studying long-term paternity outcomes in teenagers is inherently difficult.

The usual trigger for considering repair in an adolescent is a noticeable size difference between the testicles, with the affected side being smaller. Progressive loss of testicular volume on serial exams strengthens the case for intervention. When bilateral disease is present in a teenager, the concern is greater because neither testicle is spared the effects of venous pooling. A watch-and-wait approach with regular ultrasound monitoring is reasonable for mild bilateral varicoceles in adolescents who show normal testicular growth. But if there is evidence of testicular asymmetry or declining volume on either side, the threshold for surgical referral drops.

Varicocelectomy Versus Assisted Reproduction

Couples dealing with varicocele-related infertility sometimes face a choice: repair the varicocele and try to conceive naturally, or skip straight to in vitro fertilization or intracytoplasmic sperm injection. A cost-effectiveness analysis found that surgical varicocelectomy is more cost-effective than going directly to assisted reproduction for varicocele-associated male infertility.²⁶ The reasoning is straightforward: varicocelectomy is a one-time procedure with a relatively modest price tag, while assisted reproduction often requires multiple expensive cycles. If repair can bring sperm parameters up enough for natural conception, the savings are substantial.

That said, the calculus shifts depending on factors like the woman’s age and whether there are additional female fertility issues. For a couple where the woman is over 37 or has her own fertility challenges, waiting six to twelve months for sperm parameters to improve after varicocelectomy may not be a practical option. In these situations, repair and assisted reproduction are not mutually exclusive. Some clinicians recommend proceeding with varicocelectomy to improve the sperm available for IVF or ICSI, since better sperm quality can improve outcomes even with assisted techniques. The DNA fragmentation caused by varicoceles, for instance, can reduce success rates with assisted reproduction, so repairing the underlying problem still has value even when natural conception is not the primary goal.