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Hydrocele – in boys

Patient information A-Z

What is a hydrocele?

A hydrocele is a fluid filled sac which lies alongside the testis within the scrotum.

During pregnancy, boy’s testicles are formed inside the babies’ abdomen and before birth the testicles descend down into the scrotum. A hydrocele develops when the passage through which the testicles descend into the scrotum fails to close completely. Fluid from inside the abdomen can then flow through the passage into the scrotum causing the scrotum to appear swollen.

A hydrocele can occur on only one side (‘unilateral’) or on both sides (‘bilateral’).

What are the signs of a hydrocele?

A hydrocele makes the testicle / scrotum look swollen and feel like a balloon filled with water. The testicle is not painful. The amount of swelling observed can change over the course of the days / on different days.

Your doctor will confirm the diagnosis of a hydrocele by feeling your son’s scrotum. Scans are not usually required as long as the underlying testis can be felt and examined easily.

How is a hydrocele prevented?

There is no way of preventing a hydrocele. It is not due to anything a mother did, or did not do, during pregnancy.

How is a hydrocele treated?

In many cases, during the first years of life the passage may close spontaneously and so the hydrocele resolves without any treatment being required. If your son’s hydrocele does not resolve on its own, an operation will be offered.

The operation to correct the hydrocele is called ‘Ligation of the Patent Processus Vaginalis (PPV Ligation)’ and is carried out under general anaesthetic. The surgeon will make a small cut in the groin area, locate and close the passage. The wound is stitched on the inside of the skin so you will not be able to see any of the stitches. All stitches are dissolvable. Sometimes paper tapes (called ‘steri strips’) are also applied.

Local anaesthetic will be used at the end of the operation so that when your son wakes up he will usually experience little discomfort.

If your son has a hydrocele on both sides both can be operated on at the same time.

Before admission to hospital

  • Preoperative assessment: You will be asked to complete a ‘health screening questionnaire’ when your child is added to the waiting list; this will be completed immediately after your appointment if your child was seen in one of our clinics at Addenbrooke’s or, over the telephone if your child was reviewed in one of our outlying clinics.
  • Purchasing suitable painkillers: It is important that you purchase some children’s pain killers such as Paracetamol (e.g. Calpol) and Ibuprofen before admission to hospital so that you have these available at home after discharge.
  • If your child becomes unwell: If your child has a cold, cough or illness such as chicken pox the operation will need to be postponed to avoid complications. Please telephone us (the telephone number is provided at the end of this leaflet) to discuss, prior to coming to hospital.
  • Starvation times: Your child will not be able to eat and drink before the operation. Specific advice about this will be given on the booking letter once a date for surgery is confirmed.

Admission to hospital

Depending on your child’s age and any underlying conditions (e.g. epilepsy) you will be asked to bring your child to either the day surgery unit or one of the children’s wards on the morning of the operation. You will be seen by nursing staff, your doctors and an anaesthetist (who puts your child to sleep for the operation). You will be able to be present while your child goes to sleep and may also be present in the recovery area when your child wakes up.

After the operation

  • Once your son is fully awake he will be able to have a drink and then something to eat.
  • Painkillers (called ‘analgesia’) will be given as needed (usually Paracetamol and / or Ibuprofen).
  • Most boys who have had a hydrocele repair will be able to go home on the same day as their operation.
  • If your child does need to stay overnight in hospital we will provide a bed for a parent to also stay if you wish to do so.

After the operation you may not see an immediate change in appearance because of the swelling that is evident. The swelling may take a few weeks to completely resolve.

What are the complications of a hydrocele repair (PPV Ligation)?

Complications from this operation are rare. Rare complications include:

  • Infection
  • Recurrence of the Hydrocele
  • Injury to vas or blood vessels
  • Testicular ascent

Very occasionally, although the surgeon could only detect a hydrocele on one side, a hydrocele later becomes evident on the opposite side and so your son then needs to undergo a hydrocele repair on that side too.

Discharge advice

  • Your child’s wound should be kept clean and dry; they should not be bathed for five days after the operation (wiping over the area with warm water is fine).
  • We advise that your child wears loose fitting clothes for a few days after their operation. Denim trousers for example can rub on the wound and make it sore.
  • Boys may find some physical activities (such as PE at school, bicycle riding and swimming) uncomfortable and should therefore refrain from these for one to two weeks.
  • Paracetamol (‘Calpol’) and/or Ibuprofen (‘Brufen’) should be given to prevent pain. Do follow the instructions on the bottle.
  • Occasionally a wound can become infected. If your child’s wound becomes red or there is increased tenderness, contact your GP.


During your child’s hospital visits he will need to be examined to help diagnose and to plan care. Examination, which may take place before, during and after treatment, is performed by trained members of staff and will always be explained to you beforehand. A chaperone is a separate member of staff who is present during the examination. The role of the chaperone is to provide practical assistance with the examination and to provide support to the child, family member / carer and to the person examining.

Follow up

Surgical follow up is not always required but, where this is advised, review will take place three to six months after surgery to check for healing of the wound, ensure there has been no recurrence and, for testicles to be checked for size, symmetry and to ensure there has been no testicular ascent. Review may be held in the children’s outpatient clinic at Addenbrooke's, at one of our outlying clinics or via your GP. You will be informed at the time of discharge whether your son requires a follow up review and if so, where and when your child’s review is scheduled for.

For further information / queries please contact:

The ward you were on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Your nurse specialist: 01223 586973 (Mon to Fri 08:00 to 18:00)

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151