'Sleep Sex' Unromantic, Even Dangerous

Sleep Sex

Medically Reviewed by Gary D. Vogin, MD
4 min read

Until recently, "sleep sex" -- the forceful initiation of relations while in the unconscious state of sleep -- was kept hush-hush by most couples who had experienced it.


"Such behavior is not often mentioned to physicians because of feelings of shame of patients and bed partners," writes Christian Guilleminault, MD, professor of psychiatry and behavioral sciences at Stanford University in Palo Alto, Calif., who published a number of case studies on the subject in the March/April 2002 issue of Psychosomatic Medicine. "But just this morning, I have five emails asking how to get help for this."


On his website (www.sleepsex.org/) Michael Mangan, PhD, an adjunct professor of psychology at the University of New Hampshire in Durham and author of the e-published book, Sleepsex: Uncovered, elicited dozens of descriptions of this behavior from respondents on the Internet.


"My husband has a difficult time falling asleep at night," wrote one woman. "Within that first hour after he finally falls asleep, he will initiate sex with me. He is a very different person while doing this, much more aggressive, groping and playfully biting me. I used to think he was awake and doing this consciously until I would confront him the following day and he wouldn't have any recollection of what he did."


This woman goes on to say that they came to like this aspect of their relationship, but this is not always the case. Another respondent's 16-year-old sister awoke to find their 26-year-old brother-in-law on top of them. "He swears he doesn't remember doing anything like that at all," Mandan's correspondent writes, "and I believe him." Other cases have been documented of sleeping males accosting young children, and legal action has resulted.


In some of the cases described by Guilleminault, sleep sex can be "rape or rape-like behavior." In one case, the bed partner was advised to sleep in a locked room until the patient could be properly diagnosed and treated.


Sleep sex is not limited to men. In several cases in the Stanford study, women had started moaning ("with sexual undertones," the researchers noted) within a few minutes of falling asleep. In another case, a woman had started fondling themselves violently and compulsively while sound asleep.


Another study at Stanford, Guilleminault says, indicated that as many as 2% of the general population has become violent while asleep. "We think 1% of the population may have sleep sex," author Mangan says.

"Parasomnias" are disorders that intrude into the sleep process and create disruptive sleep events. They fall into several categories, including arousal disorders, sleep-awake transition disorders, and parasomnias related to REM (rapid eye movement or dreaming period) sleep.

Sleep sex, which is also known as SBS (sexual behaviors during sleep), has yet to be formally categorized as a parasomnia, although that may soon happen. The best-known parasomnia is sleepwalking, which is thought to afflict as much as 18% of the population. As is well known, sleepwalkers can venture out of the house into traffic and even walk through plate glass windows, harming themselves.

In the Stanford study, all subjects were evaluated in sleep labs and kept logs. Their medical records and medications and alcohol intake also were charted. The sex was categorized by severity. "Annoying to bed partner but not harmful" was one grouping, which consisted of sexually related sounds that could be heard outside the bedroom. The second category, "annoying to bed partner and at times harmful," referred to masturbation activities. "Harmful to bed partners and others" was the most serious category, which applied to seven cases. Force and brutality characterized these encounters.

Many times, people who engage in sleep sex have a history of other sleep disorders such as REM behavior disorders, apnea, bed-wetting, and sleepwalking, to name a few. Some have seizure disorders. All this suggests neurochemical disorders in the brain.

We really don't understand this too well," says Guilleminault. "What we are doing here is more neurology than psychiatry."

Researchers do know that during REM behavior disorders, patients are in a different state of consciousness. "They are confused and don't see reality," he says. All of these behaviors could come from abnormal brain activity, though in some cases people may not experience the muscle laxness that is supposed to come during REM sleep, which can lead to forceful behavior they would otherwise be too weak to initiate. "These people exhibit slower brain waves," he says, suggesting confusional arousal. There can also be abnormal breathing, resulting in less oxygen and a more confused mental state.

Mangan likens sleep sex to a dissociative state, similar to multiple personalities. "Asleep, this is essentially a different person," he says.

Fatigue and stress, as well as drug and alcohol use, can precipitate incidents, Mangan says (which is borne out by a study done in Canada). Apparently, sexual denial or frustration (or in the case of eating, being on a diet) does not have much to do with these behaviors.

Though lacking a complete explanation for sleep sex, doctors can still treat it successfully. If a person has a seizure disorder that is contributing to the behavior, that can be treated. Otherwise, clonazepam, in the benzodiazepine family, has proved helpful. Consult a physician.

"We are at an interesting point in history," comments Mangan. "We are watching a diagnosis emerge. Some people automatically reject sleep sex as a possibility and think people are making excuses, but we have to be careful of making snap judgments."