The effect of temperature on sperm quality mainly refers to the effect on the temperature of testes and epididymis, which changes the quality of sperm, because male testes are sensitive to high temperature, and a 1-2 degree rise in scrotal temperature will inhibit sperm production. This is because in the spermatogenesis process of human testes, a relatively low temperature environment is needed. Through the regulation of scrotal temperature by a large number of sweat glands and sebaceous glands on the surface of the scrotum, the testes are always at about 35℃. Some scientists have done such a test, the hobby of using steam bath men, repeatedly observe their sperm quantity and quality, the results found that after several steam bath, the number of sperm can be reduced, sperm vitality has also been reduced, the number of immature sperm and deformed sperm will also increase. It was also observed that the sperm quality changes of some men who love hot baths, and it was found that those who took hot baths 3-4 times a week with the water temperature above 40℃ had a significant increase in the number of deformed sperm heads and immature sperm, thus indicating that the increase in scrotal temperature can have a direct effect on the quality of sperm. The mechanism by which high temperature affects testicular spermatogenesis is mainly that a sustained high temperature environment can cause biochemical changes in microcirculation, oxygen metabolism and enzyme activity in the testes, which can lead to germ cell damage, such as high sperm malformation rate, reduced viability and density. Below we introduce common diseases that can cause elevated scrotal and testicular temperatures, as well as factors such as lifestyle habits and occupational environment. Cryptorchidism If the testicles stay in the groin and cannot descend to the scrotum due to embryonic development disorder, it is called cryptorchidism. It is one of the causes of male infertility because of the higher temperature in the abdominal cavity, which affects the process of sperm production. Varicocele Varicocele is a pathological phenomenon in which the trapezoidal plexus of the spermatic cord has poor reflux due to various reasons, or the backflow of blood caused by damage to the venous valves, resulting in local venous dilatation, tortuosity and elongation. The clinical manifestations are thickening of the spermatic cord on the left side or both sides of the scrotum, or even in the form of masses, which often causes local discomfort or pain. The disease mostly occurs in young adults. As the varicose spermatic cord trapezius plexus surrounds the testes, the degeneration of the spermatic fascial canal in patients with varicose spermatocele makes the testicular muscle diastasis impaired, the venous blood around the testes is stagnant, the reflux of blood from the veins in the spermatic cord, the higher temperature blood in the abdominal cavity is directly perfused into the testes, the testicular temperature regulation is impaired, and the testicular temperature is increased, thus affecting testicular spermatogenesis and sperm quality. Commonly, people who work in long-term seats can lead to spermatogenic dysfunction due to poor scrotal heat dissipation, such as drivers and office workers. Some studies have shown that the rate of abnormal semen quality, such as abnormal sperm malformation, density and vitality, is significantly higher in infertile men with driver occupations than in non-driver occupations and normal men, and is more severe in those with more than 8 years of driving experience. This is related to prolonged sitting, poor blood circulation to the testicles, increased temperature, and lack of oxygen. In daily life, long-term hot baths, especially sanna baths will scrotal heat dissipation, indirectly or directly increase the testicular temperature, affecting sperm production. Chefs and welders are also a high incidence of infertility, and they are almost always affected by high temperatures. In addition, seasonal changes can also have an impact on male fertility, such as the quality of semen decreases in the summer, and this change may be related to the effect of temperature changes in spring, summer, autumn and winter on testicular spermatogenesis or the endocrine effects of seasonal changes on the human ladder. Therefore, infertile patients with abnormal semen quality who are also treated with scrotal cryogenic methods.