I often hear from parents who are concerned that their baby’s hydrocele will turn into a hernia. It doesn’t work that way.
Before a boy is born, the testicles are situated high in the back of the belly. From there, they go on a slow journey through a tube called the inguinal canal to end up in the scrotal sac. They usually arrive in the scrotum at about the 29th week of gestation. Then the slippery inguinal canal closes permanently – the walls fuse together – in the few weeks surrounding birth.
If fluid is trapped by a closed canal, the child has a hydrocele. This does not present a problem.
There is an older term, “communicating hydrocele,” used to describe the situation where the inguinal canal remains partially open, with intermittent fluid build-up. This is an inguinal hernia, and should be treated as such. The intestines just haven’t entered the canal yet.
Hydroceles are very common. Perhaps half of all newborn boys have a hydrocele, although it is often not diagnosed.
Parents often notice a bulge or swelling in the groin or scrotum. The size of the swelling does not vary throughout the day, though it does gradually decrease over time.
Hydroceles disappear within the first year of life.
Hydroceles are diagnosed based on the history and physical examination. Sometimes a hernia can be difficult to distinguish from a hydrocele. If the size of the bulge varies significantly from time to time, it is a hernia. If not, time will clarify the issue. A testicular ultrasound may also be done if the diagnosis is uncertain. If the swelling is still present at the first birthday, it should be considered to have always been a small inguinal hernia.
True isolated hydroceles require no treatment. They should not be drained. They should be followed at regular well-child examinations.
If the “hydrocele” is still present after one year, the diagnosis should be changed to inguinal hernia. The structure has not changed – only the recognition that a hernia is present.
Hydroceles are a normal variant of development, and need not be prevented.