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A hydrocele is a very common condition affecting boys, where a fluid-filled sac develops inside the scrotum around the testis, making it look swollen. It is not painful and feels like a balloon filled with water.

One or both sides of the scrotum can be affected. Before your baby is born his testicles develop in the abdomen, and before birth they move down into the scrotum. Usually the tube which they pass through closes off by itself, but if this does not happen, a small amount of fluid from the abdomen leaks into the scrotum. This can cause swelling on one or both sides of the scrotum.

Most hydroceles disappear on their own. Hydroceles do not cause serious problems, but they may enlarge and become uncomfortable. The testicle is not damaged by the fluid and fertility is not affected.

If the hydrocele has not disappeared by around 15-18 months of age, it is unlikely to do so and your child can have an operation to correct this.

The operation

Your child with a hydrocele will need a small operation under general anaesthetic.

Your child will come to hospital on the day of the operation and is usually home the same day. During the operation, the doctor stitches closed the canal inside the groin. The stitches are under the skin and dissolve by themselves. There will be a scar in the groin crease. The scar fades with time, but never disappears completely.

What about activity after the operation?

Your child can play normally after the operation.

Is there pain after the operation?

Your child may be uncomfortable, so will be given medication for the pain.

Ask your doctor for advice on medication and dosage, and whether your child should be restricted from any activities when home. Pain is not the only cause of distress after an operation. Fever, anxiety and hunger can all contribute.

Will your child have to come back to hospital?

Your child will need to have a check-up with the doctor after you go home. Ask about a follow-up appointment before you leave the hospital.

Please contact your GP if:

  • You are not able to control your child’s pain with the pain medication.
  • Your child becomes unwell and cannot keep down oral fluids.
  • Your child has a temperature of over 38.50 C.
  • There is fresh bleeding from the wound area.
  • The area looks red, swollen or feels hot.


  • The operation can be safely performed in one day.
  • After the operation, your child can play normally.
  • Hydroceles may look unsightly but are usually not serious.
The Children's Hospital at Westmead
Sydney Children's Hospital, Randwick
Hunter New England Kids Health

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