Male "Menstruation"-Physiological Causes and Common Triggers of Nocturnal Ejaculation

2026-05-21

Male "menstruation" --- Nocturnal emission

When males reach puberty around the age of fourteen or fifteen, as their reproductive organs gradually mature, a physiological phenomenon occurs: during sleep, a sudden ejaculation reflex causes semen to leak from the urethra. This is commonly known as nocturnal emission.

Why do young men experience nocturnal emissions?

During puberty, or sexual maturity, a man's testes rapidly enlarge and mature. At this time, the testes not only secrete male hormones, causing secondary sexual characteristics such as facial hair, a lower voice, and a prominent Adam's apple, but also produce sperm, enabling male fertility. The sperm produced by the testes are initially stored in the epididymis. When there is an excess, it overflows into the seminal vesicles through the vas deferens. However, the seminal vesicles have a limit. Although sperm are not immortal and will naturally die, dissolve, and be absorbed over time, during puberty, testicular function is very active, and sperm production always exceeds sperm mortality. Thus, the sperm count gradually increases, and when it exceeds the storage capacity of the epididymis and seminal vesicles, a phenomenon called "spontaneous ejaculation" occurs, reflexively causing ejaculation and resulting in semen leaking from the urethra-this is nocturnal emission.

Nocturnal emission in young men is a completely normal physiological phenomenon, just like menstruation in young women, and is by no means a pathological condition. Some young men, due to a lack of hygiene knowledge, are terrified of nocturnal emission, worrying that it will "deplete their vitality" or affect their development. A few young men even develop neurasthenia due to excessive worry. This is clearly asking for trouble.

For unmarried men, one or two nocturnal emissions per month is normal. Even one or two nocturnal emissions per week should be considered normal for adolescent boys. However, excessive nocturnal emissions, such as several times a week or several times every night, may be caused by certain diseases, such as acute prostatitis or seminal vesiculitis.

If this occurs, you should go to the hospital for examination and treatment as soon as possible.

While nocturnal emission is a physiological phenomenon of "sperm inflow naturally," each instance of this reflex action is triggered by certain conditioned stimuli and is not a spontaneous overflow. Factors such as excessive bladder volume during sleep, pressure on the prostate and seminal vesicles, tight underwear causing friction to the penis, poor posture during spitting, or pressure on the penis from the body or hands can all stimulate nocturnal emission. More importantly, various sexual stimuli and arousals, such as watching erotic films or reading erotic books, talking to friends of the opposite sex, taking walks, and having sexual desires, can create strong foci of excitation in the cerebral cortex. During the day, people are working and studying, and these foci of excitation are inhibited, failing to trigger reflexive activity. During spitting, the inhibitory effect of the cerebral cortex on these foci weakens, making it easier to trigger the ejaculation reflex and result in nocturnal emission. This explains why young people in passionate relationships often experience more frequent nocturnal emissions. Understanding these triggers and taking appropriate precautions to avoid them is undoubtedly very effective in reducing the frequency of nocturnal emissions.