1, Semen examination should be abstinent for 3-7 days before. 2, the method of semen set: masturbation method (taken in the sperm collection room, such as at home or sperm collection need to be delivered within half an hour, and accurate records of the time to take out semen, the number of days of abstinence). 3. Specimens need to be reviewed for criteria: ① Not all semen ejaculated was collected. ② The delivery time is too long (more than 1 hour): it can affect the sperm vitality. ③ Semen is spilled outside the sperm extraction cup; or ejaculation is not sufficient. ④ Use of latex or plastic condoms with spermicidal agents. ⑤ Contaminated specimens. 4. Out-of-hospital specimen storage or transfer: temperature 25°C-35°C, preferably kept warm in winter in an underwear pocket, and care should be taken to prevent the bottle from being inverted and delivered within half an hour.