The testes develop in the abdomen and then gradually migrate down, through the inguinal canal and into the scrotum. They have normally reached the scrotum prior to birth.
In about 5% of boys the testes have not made it out of the abdomen by birth. At this point they are called undescended testes. This can also be referred to as cryptorchidism. They might be palpable in the inguinal canal (in the inguinal region), which is not technically classed as undescended testes, although they have not fully descended at that point.
The longer the testes take to descend, the less likely it is this will happen spontaneously. Undescended testes in older children or after puberty hold a higher risk of testicular torsion, infertility and testicular cancer.
- Family history of undescended testes
- Low birth weight
- Small for gestational age
- Maternal smoking during pregnancy
Watching and waiting is appropriate in newborns. In most cases the testes will descend in the first 3 – 6 months. If they have not descended by 6 months they should be seen by a paediatric urologist. Orchidopexy (surgical correction of undescended testes) should be carried out between 6 and 12 months of age.
It is normal in boys that have not reached puberty for the testes to move out of the scrotum and into the inguinal canal when it is cold or the cremasteric reflex is activated. This is described as retractile testicles and is considered a normal variant. This usually resolves as they go through puberty and the testes settle in the scrotum. Occasionally they may fully retract or fail to descend and require surgical correction with orchidopexy.
Last updated August 2019