Causes and risks Return to top The testicles develop before birth in the abdominal cavity. Normally, they descend into the scrotum before birth.
Undescended testicle occurs when the testicle fails to move into the scrotum prior to birth.
Once a testicle has been discovered in the scrotum, it is generally considered descended even if it is temporarily retracted on a later examination. In this instance, the testicles descend at puberty. These testicles are considered a variant of normal and do not need surgical correction. Testicles that do not descend by one year of age should be carefully evaluated. Recent studies suggest that definitive surgery should be accomplished by three years of age to confirm diagnosis and to lessen the likelihood of permanent testicular damage.