A hydrocele is an accumulation of clear fluid around one or both testicles that leads to swelling in the scrotum. In adult men, this swelling can lead to the sensation of heaviness and a bit of discomfort, but the condition is actually most common in newborn babies: Approximately 10 percent of newborn males have a hydrocele.

A hydrocele feels like a small, smooth balloon filled with fluid inside the scrotum, mostly in front of the testicles or one testicle. They vary in size, and are typically painless but can cause discomfort as the size increases. Hydroceles typically resolve in six months for adults or up to a year in infants, but a doctor may take more proactive steps if the condition is causing you discomfort or disrupting your day-to-day life.

A closer look at hydroceles

In babies, the formation of hydroceles may begin before birth. When a fetus is still growing, the testicles develop near the kidneys in the abdomen. By the time of birth, the testicles drop into the scrotum via a short channel, called the inguinal canal. In this process, a sac called the tunica vaginalis, containing fluid, is formed around each