Usually, wet dreams are associated with adolescent boys. But, they are a common experience for both sexes from puberty through adulthood. The nocturnal emission is a medical term that is used for wet dreams. The nocturnal emission is when person orgasms involuntary while he or she sleeps because of a dream, which may be or may not be erotic. It is known as wet dreams because when the male has this type of dream, then he may awaken with bedding or wet clothing. This is caused by semen, the fluid containing sperm is released during ejaculation.
But, the same term is also used to refer to when a woman orgasms during sleep. The nocturnal emission is not caused by masturbation during sleep. It happens without any manual stimulation. In some studies are found that on average, 8% of dreams have some sexual content. In this study, both men and women have said that they had an orgasm in about 4% of their erotic dreams. Some people believe that nocturnal emission can reduce the sperm count in men. But, nocturnal emission is a way for the testicles to remove older sperm and help with the natural formation of new and healthy sperm in the body. 
Many people associate nocturnal emission with men, especially adolescent boys, but in fact, women can have wet dreams too. The female nocturnal emission can result in orgasm, as well as additional vaginal secretions from arousal. Men are more prone to nocturnal emission because they naturally produce several erections at night. 
Some people believe that nocturnal emission can cause a person to have lower immunity to things, such as infection or cold, but this is a myth and it is not true in fact. But, nocturnal emission can help to reduce the excess sperm in the testicles and this is a healthy function for the male’s reproductive system. The nocturnal emission is most common during puberty, but it can happen during adulthood too. The nocturnal emission tends to happen more often in puberty due to hormonal changes. Hormone levels in adults are much more consistent and this makes it less likely that they will have a nocturnal emission.
Also, nocturnal emission can be more frequent during adolescence because boys may not be frequently masturbating or having sex, so the older sperm is released during sleep instead.  Many people believe that nocturnal emission is a result of an underlying illness or medical condition, but in fact, the opposite is true. Wet dreams are a normal occurrence and they can be a sign of healthy sexual functioning. Masturbation may reduce the number of nocturnal emissions a person experiences, but it does not guarantee that a person will never experience them.
The evidence between nocturnal emission and masturbation is lacking, but a person can experiment to see if it helps in their situation. You can try masturbating before you go to bed for a week or more, followed by the same length of time without masturbating and you will see if there is a difference in the occurrence of wet dreams. Some people believe that nocturnal emission can shrink the size of a person’s penis, but there is no scientific evidence for this.
There are no natural occurrences, conditions, or illnesses that will cause the male reproductive organ to shrink. The nocturnal emission is a natural occurrence for both men and women and it cannot be controlled or stopped. The person should not be ashamed to have them. How often nocturnal emission can happen, varies from person to person.
Nocturnal Emission: Symptoms
The most common symptoms of nocturnal emission include:
- Ejaculation during sleep
- Pain in the testicles 
- Pain in the joints 
- Indigestion and constipation
- Lack of concentration
- Gastric disturbances
- Anemia and fatigue 
- General malaise
Frequent masturbation and the lack of proper sex education can lead to nocturnal emission . Also, the easy access to sexually explicit content can contribute to the occurrence of this condition. Also, hormonal changes during puberty could lead to nocturnal emission .
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