Failure of the testes to descend from the abdomen to the scrotum is called cryptorchidism (from the Greek crypto, meaning “hidden,” and orchis, meaning “testis”). This condition occurs in three to five percent of male babies born at full-term. In premature babies the number of cases of cryptorchidism increases to 30 percent. In most cases, the undescended testicle (s) move into the scrotum without medical intervention. If necessary, the testicle(s) may be moved into the scrotum surgically. Testes are generally not left in the abdomen since this may interfere with their ability to produce sperm. Furthermore, testicular cancer is more common in men with undescended testicles.