So THAT’S Why You Actually Get Morning Wood

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Ever wondered why you sometimes get morning erections? There’s actually many scientific reasons behind it, and I’m here to tell you what they are.

“Waking up with an erect penis, also known as morning wood or nocturnal penile tumescence is an entirely normal and common phenomenon that a lot of men experience,” Yoxly Health on TikTok explains.

Despite what many people think, morning erections aren’t usually caused by sexual arousal, and can be caused by factors such as “your sleep cycle (REM sleep), changes in hormonal levels, a full bladder, and even physical stimulation from a bedsheet,” mentions Verywell Health.

A more detailed look…

Still wanting to take a deeper look into how these factors could be giving you morning wood? Take a look below:

REM sleep

“During REM sleep, which is a phase of deep sleep associated with dreaming, the body’s autonomic nervous system becomes more active. This increases blood flow to the general area and can lead to an erection,” says Yoxly Health.

“Everybody has different sleep patterns,” mentions Verywell Health. “But since there are five stages of REM sleep during the night, people with penises may have four or five erections during the night, too. Each erection can last 25 to 35 minutes, though this doesn’t necessarily happen every night.”

“Everybody has different sleep patterns. But since there are usually four or five stages of REM sleep during the night, people with penises may have four or five erections during the night, too. Each erection can last 25 to 35 minutes, though this doesn’t necessarily happen every night.”

Hormonal changes

Verywell Health explains the sex hormone testosterone plays a central role in the sexual functions of people with penises.

“Research has shown that testosterone helps facilitate nearly every facet of an erection,” they say. “From the activation of nerves that stimulate the smooth muscles of the penis to the engorgement of blood in the spongy interior of the penis.”

Testosterone levels also fluctuate and tend to be higher early in the morning than in the afternoon or evening. This incidental increase can be one of the contributing factors to a morning erection.”

Having a full bladder

Verywell Health explains that people who don’t get up to pee during the night will have a full bladder in the morning. A full bladder can press on the sacral nerve, which is a group of five nerves in the lower back.

“Your nervous system helps keep your body running while you sleep. Because the sacral nerve is responsible for erections while you’re asleep or half-asleep, stimulation of the nerve from a full bladder can cause an erection.”

When to talk to your doctor…

“Morning wood is a sign that everything in your body is working properly. However, if your morning erection often lasts longer than an hour, you may want to contact your doctor,” WebMD explains. “If your erection lasts longer than four hours, you should contact your doctor. This is a condition called priapism.”

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