HealthInfo Canterbury
A hydrocele is a fluid-filled swelling in a boy's scrotum, around the testicle (or testis). Fixing a hydrocele isn't urgent, and it doesn't affect the boy's future ability to have children (fertility).
Hydroceles happen when the tunnel that runs between a boy's tummy and scrotum doesn't fully close. Usually this connection closes before birth, after a baby boy's testicles have moved down from his tummy into his scrotum.
There's normally some fluid in the tummy so if the connection doesn't fully close, the fluid will trickle down and collect in the scrotum.
Hydroceles affect around 10% of baby boys. They usually disappear before a boy is 2 years old.
Some boys with a hydrocele also have an inguinal hernia.
Hydroceles can be different sizes, and their size varies from day to day. They look like a soft spherical swelling in the scrotum with a blue or dark tinge through the skin. They usually surround one testicle, and feel like a smooth, fluid-filled balloon inside the boy's scrotum, on one or both sides. They don't hurt.
Hydroceles usually get better by themselves by the time the boy is 2, without needing any treatment. If the swelling is still there after your boy turns 2, your general practice team can refer him to a paediatric surgeon to find out if it needs to be treated.
If he has an inguinal hernia, this will be repaired at the same time as any surgery.
The operation to fix a hydrocele is done as day surgery, so your boy doesn't need to stay in hospital overnight. The surgeon makes a small cut in the boy's groin. They then close the abnormally open passage between the boy's tummy and scrotum so fluid can't drain through it again.
The surgeon then closes the cut using dissolvable stitches, which don't need to be removed. There aren't any stitch marks.
There's an extremely low risk that the wound may bleed or become infected, and your boy may need to take antibiotics. There's a very small chance (one in 1000) that the surgery may damage his vas deferens (the tube that carries sperm) or other vessels. Talk to your boy's surgeon about these risks.
Your boy should recover quickly, although he may need some simple pain relief for a few days.
Written by HealthInfo clinical advisers. Last reviewed August 2022.
Review key: HITSP-309438