  cryptorchidism (derived from the greek ÎºÏÏÏÏÏÏ, kryptos, meaning hidden á½ÏÏÎ¹Ï, orchis, meaning testicle) 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 (the majority within three months), 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 (retroperitoneal) 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 (hypoplastic) or severely abnormal (dysgenetic); #found to have vanished (also see anorchia). about two thirds of cases without other abnormalities are unilateral; one third involve both testes. in 90% of cases an undescended testis can be felt in the inguinal canal; in a minority the testis or testes are in the abdomen or nonexistent (truly "hidden"). undescended testes are associated with reduced fertility, increased risk of testicular germ cell tumors and psychological problems when the boy is grown. undescended testes are also more susceptible to testicular torsion and infarction and inguinal hernias. "usually the testicle will descend into the scrotum without any intervention during the first year of life",the a.d.a.m. medical encyclopedia but to reduce these risks, undescended testes can be brought into the scrotum in infancy by a surgical procedure called an orchiopexy. although cryptorchidism nearly always refers to congenital absence or maldescent, a testis observed in the scrotum in early infancy can occasionally "reascend" (move back up) into the inguinal canal. a testis which can readily move or be moved between the scrotum and canal is referred to as retractile. ==normal feta
Congenital_disorders_of_male_genital_organs Testicle