Hydroceles factsheet


Testicles are two glands that produce hormones and sperm after puberty. The testicles sit behind the penis shaft, inside a pouch of skin called the scrotum. 

A hydrocele is a common condition where a fluid-filled sac develops inside the scrotum around the testicles. 

During pregnancy, a baby’s testicles develop in the abdomen or belly. Before birth, the testicles move down into the scrotum through a tube that closes itself off.

If the tube does not close properly, a small amount of fluid from the abdomen can leak into the scrotum and cause swelling on one or both sides.

 Signs and symptoms

The main symptom of a hydrocele is swelling in the scrotum. Your baby’s scrotum may change in size throughout the day.

Hydroceles are not usually painful but can be uncomfortable in older children.

Go to your nearest emergency department if your child has sudden, severe pain and swelling in the scrotum. This could be a sign of a hernia or twisted testicle, also known as testicular torsion.

Testicular torsion is a medical emergency and needs treatment as soon as possible. 


Your child’s doctor can diagnose a hydrocele by doing a physical check of the scrotum and checking if anything else is causing the swelling, like an injury.


Most hydroceles will go away on their own by the time your child is 15-18 months old. If the hydrocele has not gone away by this age, your baby can have an operation to drain the fluid.

Other than discomfort, they should not cause serious problems, and your child’s ability to have children in the future should not be affected.



A hydrocelectomy is the procedure used to remove a hydrocele from the scrotum.

Your child will be under a general anaesthetic for the procedure, meaning they will be asleep and will not feel any pain.

In the hydrocelectomy, the surgeon will cut into the scrotum to close the tube and remove the sac of fluid. The cut will be closed with stitches that will sit under the skin and dissolve into the body over time.

If your child recovers well, they can go home the same day. Before going home, your child’s doctor will make an appointment to check the scrotum in about a week, and you will be given information about pain relief.

Your child must rest at home, limit their activity, and carefully use ice packs on the scrotum.

There will be a small scar in the crease of the scrotum after the procedure. The scar will eventually fade but will not go away completely.

When to seek help

See your local doctor as soon as possible, or head to your nearest emergency department if your child:

  • cannot manage their pain, even with medication
  • becomes unwell and cannot keep down fluids
  • has a temperature of over 38.500 C
  • has bright, red blood coming from the scrotum
  • looks red, swollen or feels hot in the scrotum.

Go to your nearest emergency department if your child has sudden, severe pain and swelling in the scrotum.

Last updated Friday 9th February 2024


This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2024