Understanding Cryptorchidism: Causes, Risks, and Treatment

If only one testicle, usually the left, has descended into the scrotum by puberty, it is called cryptorchidism. This condition is fairly common, occurring in about 3% of full-term male infants and 30% of premature male infants. In up to 75% of these infants, the testicle will descend spontaneously into the scrotum during the first year of life, usually within the first 6 months.

Only about 1% of males have an undescended testicle after puberty. An undescended testicle is at increased risk of cancer and should be surgically moved into the scrotum during childhood.