If the opening between the abdominal cavity and the scrotum has not closed properly and completely, abdominal fluid will pass into the sac around the testis, causing a mass called a communicating hydrocele. As many as half of all newborn boys have this problem; however, it usually disappears within one year without any treatment. Although most common in newborns, hydroceles also can develop later in childhood, most often with a hernia.
If your son has a hydrocele, he probably will not complain, but you or he will notice that one side of his scrotum is swollen. In an infant or young boy, this swelling decreases at night or when he is resting or lying down. When he gets more active or is crying, it increases, then subsides when he quiets again. Your pediatrician may make the final diagnosis by shining a bright light through the scrotum, to show the fluid surrounding the testicle. Your doctor also may request an ultrasound examination of the scrotum if it is very swollen or hard.
If your baby is born with a hydrocele, your pediatrician will examine it at each regular checkup until around one year of age. During this time your child should not feel any discomfort in the scrotum or the surrounding area. But if it seems to be tender in this area or he has unexplained discomfort, nausea, or vomiting, call the doctor at once. These are signs that a piece of intestine may have entered the scrotal area along with abdominal fluid. If this occurs and the intestine gets trapped in the scrotum, your child may require immediate surgery to release the trapped intestine and close the opening between the abdominal wall and the scrotum.
If the hydrocele persists beyond one year without causing pain, a similar surgical procedure may be recommended. In this operation, the excess fluid is removed and the opening into the abdominal cavity closed.