Hydrocele: When Does It Need Surgery?
A hydrocele is a collection of fluid around the testicle that causes swelling of the scrotum. Many hydroceles are painless and do not require treatment. However, surgery may be considered when the swelling becomes large, uncomfortable, continues to grow or starts interfering with everyday activities.
For most adults, the decision to have hydrocele surgery is therefore based on symptoms, examination findings and personal circumstances rather than size alone.[1,5]
What is a hydrocele?
The testicle is surrounded by a thin layer of tissue called the tunica vaginalis. A hydrocele develops when fluid collects between these layers.
It commonly causes a smooth, usually painless swelling on one side of the scrotum, although hydroceles can occur on both sides.
Hydroceles are generally benign. However, a new scrotal swelling should still be assessed, because other conditions—including infection, hernia, trauma and testicular tumours—can sometimes cause or accompany scrotal swelling.[5,6]
You can read more about the assessment and treatment of hydroceles on the Scrotal & Testicular Conditions page.
Does every hydrocele need surgery?
No.
A small hydrocele that is painless and not changing may simply be monitored. There is usually no medical reason to operate on an uncomplicated adult hydrocele purely because it is present.
Interestingly, despite hydroceles being common, there is currently no dedicated international AUA or EAU guideline for the management of adult hydroceles. Contemporary treatment decisions are therefore largely based on symptoms, available research, recognised urological practice guidance and shared decision-making.[1]
When should hydrocele surgery be considered?
Hydrocele repair, or hydrocelectomy, may be reasonable when the hydrocele:
causes persistent discomfort, aching or heaviness
becomes large or continues to increase in size
interferes with exercise, work, clothing or sexual activity
makes examination of the underlying testicle difficult
causes substantial inconvenience or concern for the patient
repeatedly returns following drainage
has features that require surgical assessment after examination or imaging.[1,5]
There is no single size at which a hydrocele automatically requires surgery. A relatively large hydrocele that causes few problems may sometimes be observed, while a smaller hydrocele causing significant symptoms may reasonably be treated.
Do I need an ultrasound?
A doctor can often suspect a hydrocele from examination alone. A scrotal ultrasound is commonly arranged when the diagnosis is uncertain, the testicle cannot be examined properly, or another cause of swelling needs to be excluded.[6]
This is particularly important with a new lump or change within the testicle itself.
Sudden severe testicular or scrotal pain is different from the usual presentation of a hydrocele and requires urgent medical assessment, particularly because testicular torsion must be excluded.
What does hydrocele surgery involve?
Hydrocele surgery is called a hydrocelectomy.
It is generally performed through a small incision in the scrotum. The fluid is drained and the sac surrounding the hydrocele is repaired, folded or removed depending on its size and anatomy.
Several surgical techniques are used. Published research suggests that recurrence is generally low following surgical treatment, although the exact risk varies between studies and operative techniques.[3,4]
Most procedures are performed as day surgery, although individual circumstances can change the planned hospital stay.
What about draining a hydrocele with a needle?
Simply draining a hydrocele removes the fluid but does not necessarily treat the sac that produced it, so the hydrocele commonly fills again.
Aspiration with sclerotherapy—where the fluid is drained and an agent is used to encourage the sac to close—is another option in selected patients.
A 2023 systematic review of five small randomised studies found substantially more recurrence following aspiration and sclerotherapy than following hydrocelectomy. The authors suggested that aspiration and sclerotherapy may be particularly relevant for people who have a higher surgical risk or wish to avoid surgery.[2]
The best option therefore depends on the hydrocele, general health, anaesthetic risk and the patient's priorities.
What are the risks of hydrocele surgery?
Hydrocelectomy is a commonly performed operation, but it should not be regarded as risk-free.
Potential complications include bruising and swelling, bleeding or haematoma, wound infection, fluid collection, persistent discomfort, recurrence and, rarely, injury to structures surrounding the testicle.
Published complication rates vary depending on how complications are defined. In a large Finnish multicentre study of 866 hydrocele operations, 16.1% of patients experienced a moderate or severe complication within 90 days.[3] This figure comes from a retrospective healthcare-system study and should not be assumed to represent the risk for every individual patient or surgical setting.
Another study comparing 276 hydrocele operations reported a 6% rate of repeat surgery for recurrence and an overall complication rate of 11.6%, with differences between operative techniques.[4]
Your individual risks depend on factors such as hydrocele size, previous scrotal surgery, medications, medical conditions and the surgical approach.
What is recovery like after hydrocelectomy?
Bruising and swelling are normal after hydrocele surgery and can initially make the scrotum look larger rather than smaller.
Supportive underwear is often helpful. Most patients gradually return to normal daily activities, but strenuous exercise, heavy lifting and cycling usually need to be avoided during the early healing period.
Swelling can take several weeks to settle, particularly after treatment of a very large hydrocele.
More detailed information about hydrocele repair and other scrotal operations is available on the Scrotal & Testicular Surgery page and through the Patient Information Leaflets.
When should I see a urologist about a hydrocele?
Consider assessment if you have persistent or increasing scrotal swelling, discomfort, difficulty examining the testicle yourself or uncertainty about the diagnosis.
The first step is not necessarily surgery. Assessment can help determine whether the swelling is actually a hydrocele, whether an ultrasound or other investigation is required, and whether observation, drainage or surgery is the most appropriate option.
Patients seeking assessment in Brisbane can request an appointment to discuss their individual circumstances.
Take home message
A hydrocele does not automatically need surgery.
Observation is often appropriate when it is small, stable and not troublesome. Hydrocelectomy becomes more reasonable when the hydrocele is causing discomfort, increasing in size, interfering with normal activities or making assessment of the underlying testicle difficult.
The decision should balance how troublesome the hydrocele is against the potential benefits, limitations and risks of treatment.
References
Forss M, Bolsunovskyi K, Lee Y, Kilpeläinen TP, Aoki Y, Gudjonsson S, et al. Practice variation in the management of adult hydroceles: a multinational survey. Eur Urol Open Sci. 2023;58:1-7. doi:10.1016/j.euros.2023.09.005.
Shakiba B, Heidari K, Afshar K, Faegh A, Salehi-Pourmehr H. Aspiration and sclerotherapy versus hydrocelectomy for treating hydroceles: a systematic review and meta-analyses. Surg Endosc. 2023;37(7):5045-5051. doi:10.1007/s00464-023-10143-5.
Mäki-Lohiluoma L, Kilpeläinen TP, Järvinen P, Söderström HK, Tikkinen KAO, Sairanen J. Risk of complications after hydrocele surgery: a retrospective multicenter study in Helsinki metropolitan area. Eur Urol Open Sci. 2022;43:22-27. doi:10.1016/j.euros.2022.06.008.
Tsai L, Milburn PA, Cecil CL 4th, Lowry PS, Hermans MR. Comparison of recurrence and postoperative complications between 3 different techniques for surgical repair of idiopathic hydrocele. Urology. 2019;125:239-242. doi:10.1016/j.urology.2018.12.004.
British Association of Urological Surgeons. Repair of an adult hydrocele. BAUS Patient Information Leaflet. British Association of Urological Surgeons; accessed 22 August 2026.
National Institute for Health and Care Excellence. Scrotal pain and swelling: hydrocele. Clinical Knowledge Summaries. NICE; accessed 22 August 2026.
Medical disclaimer
This information is provided for general educational purposes only and does not replace individual medical advice, diagnosis or treatment. The appropriate investigation and treatment of a hydrocele depends on your symptoms, examination findings, medical history and individual circumstances. Surgery has potential benefits, limitations and risks, and outcomes vary between patients. If you develop sudden severe scrotal or testicular pain, rapidly increasing swelling, fever or other concerning symptoms, seek urgent medical assessment.
