What is cryptorchidism?

Cryptorchidism, or undescended testicles, is a condition in which one or both testicles are not in the scrotum at birth. Symptoms are an empty scrotum without testes that cannot be felt or testes that can be seen or felt in another place. The treatment can be based on medication or surgery.


Cryptorchidism is a relatively common condition. The testicles develop inside the abdomen before birth, and as the fetus (unborn baby) grows, the testicles move down and into the scrotum. This is usually complete before birth. This is the most common cause of a testicle not being inside the scrotum, though it is possible, that the testicle has not formed at all. The causes of cryptorchidism are not well understood, but it is probable that many factors occur together to cause this condition. Some factors which increase the risk of having undescended testicles include a small size or low weight at birth, being a twin, being born prematurely and being exposed to estrogen before birth via the mother. People with untreated testicular cryptorchidism have an high risk of developing testicular cancer.


The most common symptom is a scrotum which does not contain one or both testicles. Very commonly, the testicle can be felt in another place, such as in the penis or groin area. An ultrasound scan to locate the testicle might be done, although this is not always successful. If neither testicle is in the scrotum, or if their are other developmental problems with the genitals, blood tests might be done to look for a hormonal cause.


Diagnosis is usually made shortly after birth, because examination for cryptorchidism (feeling for testicles in the scrotum) is a part of the routine physical examination of newborns.


In many cases, the testicle will continue to descend into the scrotum after birth. If this occurs, and the testicle stays put, no treatment is necessary. This is unlikely to occur if it is not complete by the age of 6 months. In these cases, the testicle is surgically found and placed into the scrotum. This procedure is called an orchidoplexy. Boys with cryptorchidism should undergo this procedure between the ages of 6 and 12 months. Orchidoplexy is important, as it reduces the risks of being infertile and of developing testicular cancer in later life.

Other Names for Cryptorchidism

  • Undescended testes