Men have several erections while they sleep. The process is called nocturnal penile tumescence (NPT) (or “morning wood” in slang terminology), and it occurs in males of all ages, even small children. These erections are not caused by sexual stimulation but seem to be associated with REM (rapid eye movement) sleep.

Nocturnal penile tumescence (NPT) is not a result of sexual arousal or having a dream relating to sex. Instead, it is a normal function of the male reproductive system. In fact, regular episodes of NPT are a sign that the nerves and blood supply to the penis are healthy.

If a male does not have Nocturnal penile tumescence (NPT) regularly, it can indicate a health issue, such as erectile dysfunction (ED), which involves having trouble getting or keeping an erection. Not having regular NPT can also suggest other problems with the nerves or the blood supply to the male reproductive organs.

A hormonal imbalance, such as a decrease in testosterone, can also affect how often a person experiences NPT. A lack of regular NPT can sometimes result from not getting quality sleep.

Having an erect penis when you wake is an indicator of healthy blood and nerve supply to the penis. The presence of NPT also likely indicates that you’re physically capable of getting and maintaining an erection while awake.

If you stop experiencing NPT or notice that you’re not waking up with an erect penis anymore, this may be an early sign of an underlying medical problem.

Most likely, this is a sign of physical erectile dysfunction (ED). You may have something happening within your body that’s preventing adequate blood or nerve supply for proper erectile function. You may be more likely to experience ED if you :

• are overweight
• have high blood pressure
• have high cholesterol levels
• have diabetes
• have depression

Certain physical disabilities may also make ED more likely. Medications may also affect your ability to experience morning wood. Painkillers and some antidepressant medications may prevent NPT.

NPT may become less common as you get older, but if you’re young and are not experiencing a morning erection or if your erections suddenly stop, it may be time to see your doctor.

If you are concerned about your difficulty in achieving or maintaining an erection, you should speak with your health care provider. It will be important to tell your doctor whether you have morning erections, as this may provide insight into the underlying cause of your problem. Fortunately, there are a number of effective treatments for erectile dysfunction. You just have to speak up to your doctor so you can begin to get help.