After a boy is born, parents can feel something as big and active as a peanut rice in the child’s scrotum on both sides, which is the testicles. Some parents can’t feel the testicles when bathing their children, or they can’t feel one side. You cannot feel the testicles in a boy’s scrotum because one or both sides of the testicles have not yet descended into the scrotum, but remain in the groin or abdominal cavity. This is medically called cryptorchidism. The testicles are the male reproductive glands, and their development plays a decisive role in future fertility. The optimal temperature for normal testicular development and sperm production is 35°C, and the scrotum can provide this temperature. However, the temperature in the abdominal cavity and groin is definitely higher than 35℃, causing atrophy of the varicocele in the testes and the reduction or disappearance of spermatogenic cells, which seriously affects the future fertility. According to statistics, the infertility caused by unilateral cryptorchidism is about 60%, while that caused by bilateral cryptorchidism is almost 100%, and the cancer rate of cryptorchidism is 40 times higher than that of normal testicles. At the same time, cryptorchidism is mostly accompanied by hernia, and once “entrapment” occurs, it will easily cause intestinal necrosis and testicular necrosis. In addition, as the child grows older, it will also bring serious trauma psychologically. Therefore, once a child is found to have cryptorchidism, he should be treated as soon as possible. After 6 months of birth, if the testicles still have not descended, the chances of self-descending are extremely low, so we should not wait blindly and should adopt surgery.