Cryptorchidism

Cryptorchidism means that one or both testes are not in their expected position within the scrotum. A testis may have stopped along the normal route of descent in the abdomen or inguinal canal, moved to an ectopic position, become atrophic after a vascular event, or be absent. The term nonpalpable describes an examination finding; it does not establish which of these anatomical explanations applies. Acquired cryptorchidism, also called secondary ascent, occurs when a testis that was previously documented in the scrotum later remains above it. Normal descent depends on fetal development, hormonal signalling, the gubernaculum, and an open anatomical path. Prematurity and low birth weight are associated with cryptorchidism because descent may be incomplete at birth. Spontaneous descent can occur during early infancy, but descent after 6 months of corrected age is unlikely. This age boundary is why serial documentation is useful and why continued observation beyond that point can delay effective treatment. The scrotum provides a cooler environment than the abdomen or groin. Prolonged extra-scrotal location is associated with progressive germ-cell changes and impaired future fertility potential, especially when...