For baby boys, a hydrocele can develop in the womb. Normally, the testicles descend from the developing baby's abdominal cavity into the scrotum. A sac (processus vaginalis) accompanies each testicle, allowing fluid to surround the testicles.

In most cases, each sac closes and the fluid is absorbed. However, if the fluid remains after the sac closes, the condition is known as a noncommunicating hydrocele. Because the sac is closed, fluid can't flow back into the abdomen. Usually the fluid gets absorbed within a year.

In some cases, however, the sac remains open. With this condition, known as communicating hydrocele, the sac can change size or, if the scrotal sac is compressed, fluid can flow back into the abdomen.

In older males, a hydrocele can develop as a result of inflammation or injury within the scrotum. Inflammation may be the result of infection of the small coiled tube at the back of each testicle (epididymitis) or of the testicle.

Nov. 03, 2011

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