Cryptorchidism
Cryptorchidism is the absence of one or both testes from the scrotum. It is a common birth defect regarding male genitalia. In unique cases, cryptorchidism can develop later in life, often as late as young adulthood. About 3% of full-term and 30% of premature infant boys are born with at least one
undescended testis. However, about 80% of cryptorchid testes descend by the first year of life, making the true incidence of cryptorchidism around 1% overall. Cryptorchidism is distinct from
monorchism the condition of having only one testicle. A testis absent from the normal scrotal position can be: ▪ found anywhere along the "path of descent" from high in the posterior abdomen, just below the kidney, to the inguinal ring; ▪ found in the inguinal canal; ▪
ectopic, that is, found to have "wandered" from that path, usually outside the inguinal canal and sometimes even under the skin of the thigh, the perineum, the opposite scrotum, or the femoral canal; ▪ found to be undeveloped or severely abnormal; ▪ found to have vanished. About two thirds of cases without other abnormalities are unilateral; one third involve both testes.