ABSTRACT
Undescended testis is a common abnormality, affecting 3-5 percent of males. In preterm infants, the incidence may be 20 percent or more. Many testes not in the scrotum at birth descend by 12 weeks after birth, so that by three months of age the incidence of congenital undescended testes is approximately 1-2 percent. Some testes that descend late into the scrotum may reascend later in childhood, producing an acquired variant of maldescent, known as ascending testes.
