Sexsomnia is an abnormal disruption of sleep — or parasomnia — that results in people engaging in sexual activities while they’re asleep. Like sleep-walking or sleep-talking, a person engaging in “sleep sex” — another name for sexsomnia — is unaware of their actions.

The unintended sexual activities one may engage in during an episode of sexsomnia — often occurring between “deep, dreamless sleep and wakefulness” — can range from moaning, pelvic thrusting, fondling of private parts, masturbation, and spontaneous orgasms to even initiating foreplay or sexual intercourse with another. One may seem awake during this time, but they aren’t; often, they may have a dazed, vacant expression during an episode. They are also likely to have no memory of this behavior when they’re fully awake.

However, a good old wet dream — that simply arouses one and may induce an orgasm in their sleep, but doesn’t prompt any sexual behavior — isn’t a sign of sexsomnia.

Explaining why it occurs, Carlos Schenck, a psychiatrist in Minneapolis who researches parasomnias, told LiveScience, “Eating, sex, walking, fear — all these basic instincts and primitive behaviors can be inappropriately released during sleep… [But] there’s no correlation between unsatisfied sexual drive and sexsomnia.”

Unlike other forms of parasomnia like sleep-walking or sleep-talking, though, sexsomnia is wildly controversial — especially due to the criminal consequences and trauma that might follow sleep sex if it involves an unwilling participant or witness, and constitutes sexual assault. In fact, sexsomnia has repeatedly come up as a defense in cases of sexual crimes — presenting challenges for forensic examiners to determine if the accused was conscious in that moment, and had the intent to commit a crime.

Related on The Swaddle:

Why Some People Hear Loud Noises While Trying To Fall Asleep

Sexsomnia can cause shame and distress for the person experiencing it, too, and depending on one’s situation, also make them vulnerable to exploitation.

An instance of a woman experiencing sexsomnia led to spousal mistrust. Documented in a 2021 study, this is a description of the case: “There had been episodes in which she fondled her husband, who then engaged in sexual activity with her. In the middle of it, she woke up feeling somewhat abused, because, from her point of view, he was forcing sexual intercourse during her sleep without consent. This was very unpleasant for her and led to many arguments, mistrust, and distanc[e] between the couple. The husband was feeling insecure over not satisfying her sexually, and sometimes he thought she could be betraying him with other men, since she uttered the names of other men in her sleep while acting in a sexual manner.” In this case, what prompted the couple to seek a diagnosis was the fact that their 9-year-old son was an unfortunate witness to his mother’s sexual behavior.

But on rare occasions — with open communication and awareness of the disorder — sexsomnia can become part of long-term couples’ sex lives. A woman, whose husband experiences sexsomnia, said on a podcast, “We kind of laugh about it and think it’s quite funny… [H]e does kind of wake up when it becomes a little more passionate, so if we’re both in the mood, then what’s the harm?”

Describing the time it first happened, which led to the couple discovering the disorder, she recalled, “I was fast asleep, I thought he was fast asleep, and all of a sudden, he started to get a little bit handsy with me. I tried to talk to him and [was] like, ‘what’s going on’ because I’m obviously fast asleep, and he didn’t respond, and I then realized he was unconscious… [W]hen I mentioned [it] to him the next morning, he had no recollection of it whatsoever.”

Related on The Swaddle:

How Sleeping Next to Our Partners Can Improve Our Health and Wellbeing

Often co-occurring with other sleep disorders — including sleep-walking, sleep-talking, night terrors, and sleep apnea — sexsomnia can be triggered by stress, sleep deprivation, poor sleep hygiene, substance abuse, and different mental health disorders like depression and anxiety. “The obvious triggers are anything that wakes you up… Just like making noises, touching, or turning on lights can cause someone to sleepwalk when they’re in a deep sleep, you can trigger sexsomnia [too],” explains Marri Horvat, a sleep specialist and neurologist. Like other sleep disorders, sexsomnia is genetic, too.

Research suggests that men are three times more likely than women to experience sexsomnia — one can’t be sure if the gender difference in prevalence merely reflects a stigma-influenced bias in self-reporting symptoms, though. Further, symptoms of sexsomnia are, reportedly, more pronounced and aggressive in men than in women; the latter is likely to just masturbate than involve another person.

The fact that a certain degree of stigma — and, perhaps, even lack of awareness — surrounds sexsomnia is that the first official case of the disorder was reported as late as 1986. Until 2016, less than 100 cases had been documented worldwide. Moreover, having no memory of what one did while asleep, makes it difficult for them to acknowledge that they may be exhibiting sexsomnia symptoms. Naturally, this means they may have to depend on the observations of their family members, roommates, friends, or a partner; naturally, it can lead to awkward conversations, if the observer is at all comfortable confronting them about it.

Upon diagnosis, sexsomnia can be treated through medication, lifestyle changes, and addressing underlying conditions that may be behind the onset of sleep sex in an individual. But shame and embarrassment can get in the way of seeking help, too.