Human sperm is constantly produced, and normal men can find a large number of sperm in semen even after taking sperm for a short period of time after sexual intercourse. But it is conceivable that the quantity and quality of semen contained in semen at this time are obviously not good, and it is better than the previous time. In order to unify the standards, considering the influence of semen collection time on semen quality, we generally ask patients to abstain from sex for a period of time before collecting semen.

abstinence time should be 2 ~ 7 days, preferably within 3 ~ 5 days. The number of abstinence days should be counted from the last ejaculation (whether sexual intercourse, nocturnal emission or masturbation). The length of abstinence time will mainly affect the amount of semen and sperm density, but has little effect on sperm morphology and motility.

if abstinence time is too short, semen volume is often less, and sperm density is also low. However, if the abstinence time is too long, the sperm death rate may increase due to the prolonged storage time in epididymis, which can not reflect the normal situation. Abstinence for 3 ~ 5 days basically conforms to the sexual law of most people, and the semen test results are close to my physiological situation.