After a male ejaculates, he usually returns to the normal state of semen of sperm for about 5 days. The semen we see contains two components: one component is sperm, which is produced by the testes and is always produced and can be replenished at any time; the other component is seminal plasma, which is mainly made up of secretions produced by the epididymis, seminal vesicles, prostate gland and accessory sex glands such as the paraurethral glands, of which 60% comes from the seminal vesicles, 30% from the prostate gland, or prostatic fluid, and about 10% from the epididymis and paraurethral glands. The replenishment of seminal plasma requires slow osmosis, so generally the prostatic fluid as well as the seminal fluid of the seminal vesicles can reach a state of fullness in about 5 days. This is why when doing a routine semen test for men, the second test must be done after 5-7 days after the patient has had the first test, because this will ensure that the quality of the sperm test is stable.