Nocturnal emissions are 'a nearly universal, physiological phenomenon with cultural, educational, and clinical dimensions' with a prevalence of 70%-90%, occurring most commonly at ages 13-14, and evidence does not support the historical view of them as a compensatory release under conditions of low sexual outlet.
The first nocturnal emission typically occurs between ages 12.6 and 15.6 years, most often at ages 13-14, with modest cross-cultural variation.
Prevalence of nocturnal emissions was high overall (70%-90%), particularly among adolescents, though lower rates were found in some Asian cohorts and rare occurrence was noted in individuals with neurological impairment.
Data on frequency of nocturnal emissions were scarce and inconsistent across the reviewed literature.
Evidence did not support the historical view of nocturnal emissions as a compensatory release mechanism under conditions of low sexual outlet.
Nocturnal emissions can occur with or without erotic dreams.
Findings from studies on spinal cord injury and psychogenic anejaculation confirm that nocturnal emissions can arise independently of supraspinal control.
The association between nocturnal emissions and sleep orgasms and sleep-related erections remained uncertain.
Hormonal, parental, and prenatal influences on nocturnal emissions appeared modest.
Significant educational gaps and widespread misconceptions about nocturnal emissions persist, particularly in South Asia where they are central to Dhat syndrome.
Nocturnal emissions may have clinical utility in differentiating psychogenic anejaculation and can occasionally serve as a sperm source for assisted reproduction.
A total of 157 sources were included in the systematic scoping review, which searched PubMed and EMBASE from inception to April 2025 with no exclusions based on study design.
This research systematically reviewed 157 scientific sources on nocturnal emissions (wet dreams) — involuntary ejaculations that occur during sleep — to summarize what is known about how common they are, how they work, and what they mean clinically and culturally. The review found that wet dreams are nearly universal among males, occurring in 70%-90% of people, typically beginning between ages 12.6 and 15.6 with the most common onset at ages 13-14. Contrary to a long-held belief, the evidence does not support the idea that wet dreams serve as a 'release valve' that increases when other sexual activity is absent. They can happen with or without erotic dreams, and studies of people with spinal cord injuries show they can occur even without input from the brain, suggesting they are controlled at a lower level of the nervous system. The review also highlighted important cultural and educational dimensions. Misconceptions about wet dreams remain widespread, especially in South Asia, where beliefs about semen loss are connected to a culturally specific condition called Dhat syndrome, in which men experience significant distress and health complaints related to perceived semen loss during sleep. Educational gaps about the normality of wet dreams were identified as a persistent problem across cultures. The review also found that how often wet dreams occur is poorly understood, as data on frequency were scarce and inconsistent across studies. This research suggests that wet dreams have practical clinical uses: their presence in a man who cannot ejaculate voluntarily can help doctors determine whether the problem is psychological rather than physical, and collected emissions have occasionally been used as a source of sperm for fertility treatments. The authors conclude that despite being a nearly universal part of male development, wet dreams are understudied and that higher-quality research is needed to better understand the biological mechanisms involved and to address the educational and cultural challenges surrounding them.
Maiolino G, Fernández-Pascual E, Lledó-García E, Martínez-Salamanca J. (2026). Nocturnal emissions or wet dreams: modern evidence from a systematic scoping review.. Sexual medicine reviews. https://doi.org/10.1093/sxmrev/qeag003