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Morning Erections
Definition, Causes, and Problems with Morning Erections

By , About.com Guide

Updated June 27, 2009

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Many young men, and even some older ones who haven’t found the right people to ask, are curious about morning erections. Most men have the experience, with some regularity, of waking up in the morning with an erection.

What Is A Morning Erection?

Morning erections, colloquially referred to as "morning wood" and scientifically defined as nocturnal penile tumescence (NPT) are a healthy and normal physiological response that most men experience. Morning erections would be better described as the tail end of a series of nighttime erections, as they are just the last erection in a series.

On average a healthy male will have between three and five erections in a full night sleep, with each erection lasting between 25 -35 minutes.

Causes of Morning Erections

It is a common myth that morning erections are caused by a full bladder. This is untrue. While the reason for morning erections is unknown, we do know that the erections are closely associated with REM sleep (the time in the night when you dream and brain activity changes). These erections are also associated with an increase in heart rate. It isn’t known for sure if the erections are a result of the other physiological changes, more research is required. One guess is that these erections are the bodies way of making sure everything is in good working order.

Lack of Morning Erections

Early research on morning erections did not find a difference in the morning erections of older men when compared to those of younger men. More recent research has shown a gradual decline in morning erections (some show just a decrease in the rigidity and length of time of an erection and not the frequency of getting erections).

One of the reason morning erections attracted the interest of researchers was as a tool to rule out physical causes of erectile dysfunction. If a man cannot get an erection to his satisfaction during sexual activities one of the first things a doctor will determine is whether or not he is getting full erections during the night and in the morning.

If a lack of morning erections is accompanied by a lack of overall erections it suggests a physical over a psychological cause. If you are concerned about a noticeable change in your morning erections it's something you may want to talk about with your doctor. However there are a variety of other factors that influence morning erections (including length and quality of sleep) and a change in morning erections doesn't always indicate a serious problem.

Erectile Dysfunction Medications and Morning Erections

Medications used for the treatment of erectile dysfunction (ED) including sildenafil (Viagra) and tadalafil (Cialis), can have an impact on morning erections. Both medications, if taken the night before prior to sexual activities, can result in morning erections, although morning erections occur more often when tadalafil is used.

Of course there is no reason to take a medication simply to get a morning erection, as morning erections, while they may be related to overall erectile function are not necessarily a total indicator of function or dysfunction.

Sources:

  1. Gordon, C.M. and Carey, M.P. “Penile Tumescence Monitoring During Morning Naps to Assess Male Erectile Functioning.” Archives of Sexual Behavior Volume 24, No. 3 (1995): 291-307.
  2. Rosen, R.C., Goldstein, L., Scoles, V., et. al “Psychophysiologic Correlates of Nocturnal Penile Tumescence in Normal Males.” Psychosomatic Medicine Volume 48, No. 6 (1986): 423-429.
  3. Sae-Chul, K. “Regaining of Morning Erection and Sexual Confidence in Patients with Erectile Dysfunction.” Asian Journal of Andrology Volume 8, No. 6 ( 2006): 703-708
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