Pediatric hydrocele is a condition in which fluid builds up in the scrotal sac of an infant.

This is more likely to occur in premature babies, but about 5% of all male infants will be born with a hydrocele. It is not considered dangerous and is usually not even painful.

The Anatomy of a Hydrocele

During fetal development, the male’s testicles descend from the abdomen into the scrotal sac. Each testicle is enclosed within a membrane that separates it from the scrotal wall. It is normal for there to be a layer of fluid within this membrane, and it is absorbed by the body after the testicle has descended.


Sometimes, though, this layer of fluid builds up to an abnormal amount. It forms a pocket of fluid in the scrotum that causes it to have a swollen appearance.

There are two types of hydroceles: non-communicating and communicating.

  • With a non-communicating hydrocele, the fluid sac closes normally at the top after the testicle has descended. This causes the excess fluid to be pinched off in the sac with no means of moving back into the body.
  • A communicating hydrocele still has an opening into the abdomen. The fluid can flow between the abdomen and the scrotum. Sometimes this makes the hydrocele change size over the course of the day, sometimes bigger and sometimes smaller.

Treatment of Hydroceles

  • Hydroceles often do not require treatment. The excess fluid in both the communicating and non-communicating types is usually resorbed by the body during the baby’s first 6-12 months of life. Since the condition is not painful, it is allowed to resolve on its own.
  • Occasionally, a hydrocele will persist past the one-year mark. In this case, surgical treatment may be warranted, especially if communicating, in order to prevent the possibility of bowel-containing hernia. When necessary, a hydrocele is corrected during a hydrocelectomy or hernia repair, which is an outpatient procedure.