A hydrocele is a fluid-filled sac in the scrotum.
Hydroceles are common in newborn infants.
During a baby’s development in the womb, the testicles descend from the abdomen through a tube into the scrotum.
Hydroceles occur when this tube does not close. Fluid drains from the abdomen through the open tube and gets trapped in the scrotum. This causes the scrotum to swell.
Most hydroceles go away a few months after birth. Sometimes, a hydrocele may occur with an inguinal hernia.
Hydroceles may also be caused by:
• Buildup of the normal fluid around the testicle. This may occur because the body makes too much of the fluid or it does not drain well. (This type of hydrocele is more common in older men.)
• Swelling or injury of the testicle or epididymis