It is possible for a man to have semen flow out without a physiological response. Men often reach orgasm during sexual intercourse, semen will flow out, which is a normal physiological response, but there may be no physiological response, the phenomenon of semen flow out. Usually because of a long time without ejaculation, for example, a long time without sex in the seminal vesicles semen volume is relatively large, will flow out on their own, belongs to the phenomenon of semen leakage. Most of the men’s semen leakage occurs at night, and they are often not aware of it during sleep, but if frequent semen leakage is abnormal, it may be caused by inflammation of the reproductive organs, or it may be caused by frequent masturbation. It is recommended that if a man does not have a physiological reaction, but frequent semen need to go to the hospital in time to find out the cause of targeted treatment.