The erection occurs 3 or more times during the night during REM (rapid eye movement) dreaming sleep. During this time there is more blood flow to urethra which causes the erection.
Here is A LOT of different answers i found in another question here.
More answers down below
Morning erections are technically nighttime erections which happen during Rapid Eye Movement (REM) sleep (when most dreaming occurs), although men older than sixty years may have them during even non-REM sleep. Generally, we experience four intervals of REM sleep per night. These spontaneous woodies in the wee hours are caused by specific neuroreflexes (whatever the word is called.) that are stimulated during REM sleep.
An erection has been proven to greatly relieve the pain of needing to urinate badly. The reason is because when you get an erection, a valve stops the urine from entering the urethra so that only semen can pass through the urethra during ejaculation. So the next time you're in your car in a traffic jam and you REALLY need to go... just use your imagination. Ha ha It works every time. It is partially why you have morning erections since it helps prevent you from peeing on yourself! Ever notice how difficult it is to urinate with an erection? Ever peed on yourself in bed since you hit puberty?
TRIVIA NOTE: the proper term for this phenomenon is Nocturnal Penile Tumescence!
it might be due to the dream you have been having that was perhaps about your girlfriend with no clothes on.
An alternative reasonThe reason a man gets an erection in the mornings is one way to see if he is sterile, I went to the doctors with my wife to find out and that was one of the questions on the form I was given and they told me that it is a 98% chance that I am not sterile. and I thank god for that, but it is also a build up of testosterone in the male, more than likely though you will not have it if you have had a vasectomies.
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 ErectionsIt 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 ErectionsEarly 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 ErectionsMedications used for the treatment of erectile dysfunction (ED) including sildenafil (Viagra) andtadalafil (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.
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Depending on age usually. I am 31 and have about 5 per day, more if desired. As a teenager I had anywhere from 15 to 30 everyday especially when in school. As I've gotten older erections are easier to control. I've noticed this mostly because I've recently accepted a job as a nude model. An erection during a modeling session isn't a bad thing, it would however conflict with the artists concentration and mine as well.
Erections occur as a result of sexual arousal, or often as a cycle during sleep.
any time he wants
Not in standard urination. However, after erections, men often need to urinate, this is a biological function designed to "keep the pipes clean" and free of organic materials.
Guys can get erections in the morning but girls don't.
Most if not all guys do very often. As boys and young men, about as often as they can get away with it.
Guys tend to have erections in the morning & it was poking her
often excitement.
No, it is common in most men who get random erections (erections that occur when there is no sexual physical or mental stimulation) or men who have prolonged sex with no ejaculation.
Some do some dont
They can do yes. These are called spontaneous erections or involuntary erections. They occur when blood suddenly rushes into the penis (erections are caused by blood flow into the penis). It's very common in men when they wake up in the mornings.
Men get boners (or more correctly erections) when they usually see women or if they are gay another man. Women can discharge if they are sexually aroused by looking at a man. During puberty erections may come at unusual times. Mature men generally only get erections when they are sexually aroused. If a man is homosexual, this arousal will be triggered by other men. It's possible that you, on some level, find other men to be sexually attractive. It's also possible that while you were gazing at a man, your mind was thinking about something sexual, whether related to men or women.
yes some men do, but its more of a fetish than the norm
Generic Cialis is the most suggested one as it helps impotent men get harder erections. It is important to ask with the doctor and then go ahead with the dosage of this medicament.
Physically healthy men experience several prolonged erections during sleep.