Given how much emphasis is placed on exactly how to have full-body orgasm, how to orgasm faster, and how hard it can be for certain people to climax, particularly during penetrative sex (orgasm gasp, anyone?), it might seem improbable that an orgasm could happen by accident. But, believe it or not, some people can experience an unexpected or accidental orgasm, thanks to certain types of mental arousal that can happen with or without genital touch and the presence of sensitive nerve endings in less-expected places (and we’re not talking about a prostate orgasm, mind you).

What is an accidental orgasm?

Considered one of the many, albeit lesser-known, types of orgasms, a spontaneous or accidental orgasm is “an orgasm that somebody has when they’re not actively seeking an orgasm,” says Searah Deysach, sex educator and owner of Chicago-based pleasure-product company Early to Bed. “It comes via other means than direct conscious genital stimulation.”

How common is an accidental orgasm?

There isn’t enough information to know how common an accidental orgasm is. “As a lot of things that have to do with sexual health, there’s not a lot of research,” says Deysach. What she can say is that accidental orgasms happen to a wide range of people. “They’re relatively normal in the sense that it can happen to anybody,” she says. While it’s hard to know exactly how common accidental orgasms are, Deysach says there are more people who are prone to accidental orgasms—and the surprising sensual sensations that come with it— than others.

According to sexologist Jessica O’Reilly, PhD, host of the Sex With Dr. Jess podcast and author of The New Sex Bible, if you typically become aroused with ease, you may be more apt to experience an accidental orgasm. Beyond this demographic of lucky individuals, she says the likelihood it’ll happen to you has less to do with the specific design of what’s between your legs and more to do with what’s going on between your ears. “It may be related to sexual excitability or mindfulness,” she says. “If you’re present in your body and you allow it to receive stimulation without inhibition, you might be more likely to have spontaneous orgasms.” And that’s particularly the case if you also happen to be in a physical position that can bring about unintentional pleasure, leading to arousal and stimulation, too.

Below, Dr. O’Reilly walks through the science behind the most common accidental orgasm causes, including the seemingly ordinary situations that can lead to unexpected climax experiences.

7 potential accidental orgasm causes

1. Stimulation of non-genital erogenous zones

Erogenous zones extend far beyond the genitals, including body parts like the ears and the midsection—and stimulation of any of these areas, whether in an explicitly sexual way or not, could bring about surprising sexual sensations and spark an orgasm outside of sex.

While some folks report orgasms from having the small of their backs tickled, licked, or massaged, others note the same from stimulation of their belly buttons, says Dr. O’Reilly. “The positioning of the navel in proximity to the pubic mound coupled with the density of nerve endings in the region makes this sensitive indentation a common erogenous zone,” she says. “Some people say they experience sensations in their clitoris through the belly button, which might be attributable to a nerve pathway that connects it to the spine through the pelvic region.”

2. Performing oral sex

While receiving oral sex is a common route to a (very purposeful) orgasm, giving it can be just as orgasmic for some folks, according to Dr. O’Reilly. “Some people attribute this to the stimulation in the back of their throat by a penis,” she says, “and others report being so aroused by the power of the act and their partner’s pleasure that they find themselves experiencing orgasm as well.”

3. Certain types of exercise

Occasionally, an orgasm can happen without any direct touch or stimulation by yourself or a partner—but instead through muscle flexion in nearby regions. So-called “coregasms” can occur during ab work, which can mean crunches (though 100 to 200 are typically required), pull-ups, and chin-ups, as well as not-so-ab-centric work including leg presses, leg raises, and even, in some cases, running or swimming.

On a similar note, kegel exercises can also cause spontaneous orgasm incidents, though Dr. O’Reilly says she’s not sure they qualify as accidental. “Oftentimes, we discover a pathway and then use it over and over again because it works. I’ve met many folks who can have hands-free orgasms by tensing and releasing their pelvic floor muscles. Some do so while rubbing against a mattress or squeezing a bed sheet between their legs and others use the tense-and-release method on its own,” she says.

4. Riding a bike or motorcycle

Cycle sessions (in the studio or the street) are notorious triggers of accidental orgasm, not just through the exercise pathway above but also because of the body positioning involved in cycling. “It’s no surprise that riding a bike can produce pleasurable and even orgasmic sensations, as rubbing, grinding, and squeezing on the outside [of the seat] can stimulate both the external and internal parts of the clitoris that are believed to lead to orgasm,” she says. “I’ve also seen reports of accidental orgasm from motorcycle riders (and passengers) as they rub against the seat and experience the vibrations from the engine.”

Before you sign up for a year’s worth of spin classes, however, she cautions that there is some research suggesting that frequent bike riders report adverse sexual side effects, including reduced desire and difficulty achieving orgasm. So, it’s always a good idea to get to know your body first and adjust your efforts accordingly.

5. Wearing tight pants

To be fair, you’re not likely to just have an accidental orgasm from the tightness of your plants alone. But, if they’re ultra-tight and you’re moving around in them, it becomes more likely that it’ll bring about unintentional pleasure.

“If you rub against a surface in a way that brings you pleasure, it’s possible it could lead to orgasm,” says Dr. O’Reilly. “It really depends on your preferred method of reaching orgasm, but I’m sure there are folks who can do so by simply rubbing against the seam of their jeans.” She’s also heard reports of orgasms during yoga or Pilates, and notes that the combination of tight pants and pelvic-floor exercise may produce this effect.

6. Mental arousal

Little more than imagination can take you a long way to an orgasm, whether purposeful or accidental. In her book The New Sex Bible, Dr. O’Reilly writes: “So powerful is the mind’s hold over our sexuality that some people can actually ‘think’ themselves off through fantasy and breath work. Though early sex researchers theorized a strong link between fantasy and orgasm, technological advancements now provide evidence that some women can have hands-free orgasms.”

In fact, a small 2016 study of 11 people found that simply imagining erotic stimulation of the nipples and clitoris activated the same region of the brain that lights up during actual stimulation of those regions. So, it may be possible for some folks to have unexpected climax experiences from just entering a sexual headspace.

7. Seemingly nothing at all

Perhaps one of the most intriguing accidental orgasm causes is the possibility of experiencing a spontaneous orgasm without penetration, touch, sexual thought, or exposure to stimuli—but, in most cases, that would be indicative of persistent genital arousal syndrome (PGAS). “The symptoms of PGAS span the spectrum from mild ongoing arousal to extreme, constant, and unprovoked orgasmic sensations,” says Dr. O’Reilly. “While orgasm may offer temporary relief from this persistent, unwanted arousal, some women report that the feelings of arousal return almost immediately, and this condition can be extremely distressing.”

As research in this field is in the early stages, specific causes are unknown, says Dr. O’Reilly. But PGAS is often associated with anxiety, depression, and hormonal treatments in postmenopausal women. “Treatment may include topical anesthetics and antidepressant medications in conjunction with psychotherapy,” she says. In any case, it’s a good idea to speak to your gynecologist if you suspect that you might fall into this camp.

Can you accidentally orgasm in your sleep?

Sleep can be a gateway to unexpected climate experiences, and while research is limited on why some people have nocturnal or sleep orgasms, they’re commonly thought to occur during REM sleep—the stage in which we dream—due to increased blood flow to the genitals. Sleep orgasms can be brought on by sexual arousal, much like sex orgasms, but some people can also experience it when they sleep on their stomachs because there is more contact between the bed and genitals, which increases the likelihood of genital stimulation.

While sleep orgasms are typically associated with people with penises, people with vaginas can also have unexpected climax experiences during sleep—they might just be less likely to remember it. According to Dr. O’ Reilly in a previous interview with Well+Good, this disparity might be due to penises leaving physical evidence of an orgasm—as in, ejaculations—as opposed to people with vaginas.

Are accidental orgasms always pleasurable?

According to Deysach, not all accidental orgasms are pleasurable. “I think while we think of orgasms as being this wonderful thing that is sought after, if it is something is occurring when you’re not prepared, when you’re not in a space to allow yourself to enjoy it, [or] when it’s not something you’re looking to have happen, it can be—and I’m not saying it will necessarily hurt—an unpleasant feeling,” says Deysach. As Dr. O’Reilly previously mentioned, people with persistent genital arousal syndrome can also experience distress during spontaneous orgasms, particularly among those who have more severe symptoms, which typically manifests in extreme, constant, and unprovoked orgasmic sensations.

“With anything, if it’s happening at a frequency or there’s something about [an accidental orgasm] that is causing you to be upset or concerned, you should talk to a healthcare professional about it,” says Deysach.