Nocturnal emissions are ejaculations and orgasms that occur while a person is sleeping. They can happen to men of all ages, but are most common during the early years of puberty in young adolescence. Nearly all men at one time will experience a nocturnal emission, which are often called wet dreams, and they are considered a normal part of sexual development. Ejaculations during sleep are most common during puberty, between the ages of 12 and 18. For many young adults it is one of the first signs that puberty has begun.
Most scientists agree that there is no set trigger that causes a nocturnal emission. While increased masturbation does seem to have an effect on the frequency of wet dreams, the correlation between the two is not absolute. Many young men masturbate frequently and still experience nocturnal emissions, though they usually have fewer occurrences. Conversely, some men rarely have them even if they don't regularly masturbate.
Ejaculations during sleep are most often tied to erotic dreams, but just like masturbation frequency, there is no direct link between the two. Some men will have vivid erotic dreams that lead to a spontaneous orgasm, while others will regularly have erotic dreams but never have a nocturnal emission. Some may wake up during their nocturnal emission, but it is just as common to sleep through it entirely. Others may not even achieve an erection during a nocturnal emission. It simply varies from person to person.
While nocturnal emissions are generally thought to be strictly a male phenomenon, women can experience them as well. Just like men, women can have erotic dreams, and they can sometimes lead to orgasms. Unlike men, the evidence of a female orgasm while sleeping is less obvious, and therefore not discussed as much. Also, women tend to have fewer wet dreams than men because their genitals are usually less susceptible to touching and stimulation while sleeping than male genitals can be.
Most medical doctors and child psychologists will say that a parent should not scold a child for experiencing a nocturnal emission since they have no control over them. If a child asks about nocturnal emissions, doctors usually recommend that the parent explain they are a normal part of growing up. A young adult entering puberty is often self-conscious about the changes their body is going through. They should be reassured that what they are experiencing is not unusual and that others their age are most likely having nocturnal emissions as well.