The occurrence of sexsomnia — making advances and performing sexual acts while asleep — appears to be more common than once thought.

Researchers have found that almost eight per cent of patients at Toronto’s University Health Network sleep disorders clinic reported they initiated or engaged in sexual activity with a bed partner while asleep. The prevalence of sexsomnia was almost three times higher in men (11 per cent) than in women (four per cent). Those with sexsomnia were twice as likely to report using illicit drugs (15.9 per cent versus 7.7 per cent), concluded the study.

While the specific cause of sexsomnia has not been pinned down, sleepiness and sleep deprivation were believed to be factors, as are alcohol consumption and stress.