Why do undescended testicles occur in cryptorchidism?

In the context of biology, cryptorchidism is a condition where one or both testes fail to descend spontaneously from the abdominal cavity into the scrotum by the time of birth.12

Under normal development, the testes are formed in the abdomen and are stimulated by androgens to descend into the scrotum, typically around the seventh to ninth month of fetal life. When this process is interrupted, it is generally due to one of two primary factors:32

• Mechanical difficulty: Physical obstructions or anatomical issues may prevent the testes from moving along their normal path into the scrotum.2
• Hormonal defect: A lack of appropriate hormonal stimulation—specifically the androgens required to trigger and guide the descent—can result in the testes remaining within the abdominal cavity or the inguinal canal.132

While some cases resolve spontaneously in early infancy, persistent cryptorchidism often requires gonadotropin therapy or surgical intervention to move the testes into the scrotum, as undescended testes are at higher risk for injury, infertility, and testicular cancer.12