(1) Infertility As we know, under normal circumstances, the temperature of the scrotum is lower than the body temperature by about 2℃~3℃, and this temperature difference is one of the important conditions to ensure spermatogenesis. This temperature difference is one of the important conditions to ensure spermatogenesis. However, in bilateral cryptorchid patients, since the testes are not in the scrotum, the temperature difference with the body temperature disappears, and the increase in temperature can make the testicular epithelium atrophy, thus hindering spermatogenesis and producing infertility. Unilateral cryptorchidism from the second year of life of infants, the opposite side of the normal position of the testicle is also damaged, so untreated, may also affect fertility. (2) Hernia is usually caused by incomplete descent of the testis, which prevents the peritoneal sheath from closing and causes the abdominal contents to descend by a route. Hernia as a complication of cryptorchidism is reported to be around 50% in China and up to 66%-97% in foreign countries. (3) Torsion of the spermatic cord may be caused by over-contraction of the levator muscle, underdevelopment of the testicular lead, and excessive movement of the testis. According to statistics, about 50% of patients with spermatic cord torsion suffer from cryptorchidism. (4) Testicular trauma The testis located in the inguinal area is easily traumatized because of its superficial position and the posterior inguinal wall is harder and less elastic than the scrotum, which lacks cushioning. (5) Malignant changes The chance of malignant changes in cryptorchid testis is more than that of normal testis, about 30-50 times. In addition, unilateral cryptorchid testis patients on the other side of the testis tumor incidence is also higher than normal people. (6) Mental trauma The absence of testicles in the scrotum may cause mental trauma and low self-esteem.