Is it normal to wake up with an erection sometimes?

Yup! “Morning wood” is completely normal and very common. Many people with penises actually have 3-5 erections every night! You probably just don’t notice these because you’re asleep.

Erections occur when hormones signal your body to send blood to your penis, making it “hard.” Sometimes, erections happen when you’re thinking about sex or something that turns you on, or when you’re sexually stimulated (such as touching your penis, nipples or another part of your body). But they can also happen randomly or for no reason at all, especially during puberty!

Nocturnal penile tumescence (NPT, as morning wood is officially called) can happen for a few different reasons.

Even though you probably don’t notice it, erections often happen during a stage in the sleep cycle called REM. This is when you dream. During REM, your parasympathetic nervous system (which helps your body relax and controls processes in your body like digestion) becomes active. This can lead to an erection.

Since it’s common to wake up just after REM sleep, it’s also common to wake up with an erection. You don’t have to be dreaming about sex or feel aroused to get an erection while you sleep (though this can also happen).

In addition, when you move in your sleep you may touch your penis without realizing it. This may sometimes be enough stimulation to cause an erection.

Usually, morning wood goes away a few minutes after you wake up.

If it lasts for longer than an hour, talk to a doctor. You should also talk to a healthcare provider if you suddenly stop getting erections in the morning, or if they hurt. These can be signs of medical conditions.

Generally, though, there’s no reason to be embarrassed or worried about morning wood. In fact, NPT is a sign that your body is working like it should be!

If you have any more questions about your body and are 10-22 years old near NYC, you can make an appointment at the Mount Sinai Adolescent Health Center for completely free, confidential, comprehensive healthcare. No judgment, no charge.

A version of this post was originally published in September, 2018.