1. Nocturnal orgasms aren’t just a male phenomenon—many women have them too! In Alfred Kinsey’s groundbreaking research on female sexuality, he found that 37% of the women he surveyed had at least one such orgasm by their mid-40s. Read more about female nocturnal orgasms here.

2. “Morning wood” isn’t just for men either—women often wake up with the clitoral equivalent of morning wood! People naturally experience 4-5 penile or clitoral erections per night as they cycle in and out of REM sleep.

3. While we’re on the subject of sleeping, research has found that people who sleep on their stomachs report having more sex dreams. Why? Perhaps because sleeping in this position puts physical pressure on the genitals that gets transferred into our dreams.

4. Contrary to popular belief, the risk of having a heart attack during sex is very low. Interestingly, however, research has found that when heart attacks do occur during sex, they’re more likely to happen to men when they’re cheating compared to when they’re having sex with a spouse. Why? Perhaps cheating induces psychological distress (e.g., feelings of guilt, anxiety, or stress) that, in turn, negatively affects cardiovascular function.

5. Some women experience orgasms from nipple stimulation, and there’s a good reason for this: research reveals that stimulation of the nipple activates the same region of the brain (the genital sensory cortex) as stimulation of the vagina, cervix, and clitoris. Learn more about the “nipplegasm” here.

6. Orgasms aren’t just for humans—animals have them too. Of course, we don’t know whether the psychological experience of orgasm is the same among animals; however, the physical experience (at least in non-human primates) looks very similar, right down to the O-face.

7. Studies suggest that the depth of the average vagina is a little shorter than the depth of the average penis. Perhaps this is why most women report that longer penises do not necessarily increase their sexual pleasure.

8. Research has found that the distance between a woman’s clitoris and her vaginal opening is associated with her likelihood of having an orgasm during intercourse. Here’s a handy rule of thumb: when the distance is less than the width of her thumb, a woman is more likely to reach orgasm without the need for added clitoral stimulation.

9. When we masturbate, our perception of what is sexually attractive and desirable changes. In fact, research has found that heightened sexual arousal achieved through masturbation can make almost anything and anyone seem more sexually appealing. There are some fascinating and important implications of this finding for the development of unusual sexual interests.

10. This is quite rare, but some people experience sneezing fits upon reaching orgasm. There is also a variant of this condition in which an individual sneezes simply upon experiencing sexual arousal.