What happens 'down below' while you sleep

Women, like men, can wake up aroused - and there's a biological reason for it. Photo / 123rf

Have you ever wondered what happens to your vagina while you sleep? Probably not.

You'll probably be surprised to know that, while you're resting, your nether regions are actually very busy.

In fact, a vagina's "nighttime activity" is quite similar to a man's penis activity in the quiet hours.

There's even a scientific name for all the work vaginas do while we sleep: "nocturnal clitoral tumescence" (NCT). Men's penis activity is called "nocturnal penile tumescence", which is way easier to identify.

This, in layman's terms, translates into "morning glory" for men but very little is known about the same phenomenon happening to women.

The reality is, women have their own version of "morning glory", and it happens on and off all through the night.

During sleep and when waking up, much like the penis, a woman's clitoris swells up.

Scientists believe this happens more during the REM phase of sleep, due to a lack of norepinephrine (which prevents blood flow to the genitals).

On an average night, a woman will go through four to five REM phases, which means a lot of clitoris swelling.

NCT comes with an added bonus for women: orgasms in your sleep.

According to Dr Sergio Diez Alvarez, director of medicine at Maitland and Kurri Kurri hospitals, University of Newcastle, men don't experience this positive side-effect.

"The interesting thing that's different to males is women are more likely to have an orgasm at the same time during the dream phase," he told Mamamia.

Sometimes a woman will remember these orgasms, others she won't. But it does explain why women can wake up feeling aroused in the morning.

People on Reddit have come up with a female version of morning glory: "morning bean".