The process of spermatogenesis occurs mainly in the seminiferous tubules of the testes and develops from spermatogonia. Spermatogonia are arranged in layers in the seminiferous tubules. When the male becomes sexually mature, under the stimulation of androgen, they divide and develop into primary spermatogonia, and then undergo several mitotic divisions and meiotic divisions to produce spermatocytes, which at this time only have half of the genetic material of a normal cell. Spermatocytes become spermatozoa after developmental metamorphosis and differentiation of the head and tail. The spermatozoa run in the epididymis and mature over a period of about 15 days, acquiring the ability to move and fertilize, and are then stored in the epididymis and vas deferens, to be discharged when ejaculation occurs. Sperm production is mainly regulated by sex hormones. When sex hormones are not secreted sufficiently, it can lead to a decrease in the number of spermatozoa and their motility, which may result in male infertility. In addition high testicular temperature, such as cryptorchidism; inflammation and infection, such as orchitis and epididymitis; and impaired blood circulation in the testes, such as varicocele, can affect the spermatogenesis process and lead to a decrease in sperm quality.