How do erections work?

Let's get to grips with this important issue.

How do erections work?

An erection is the stiffening and rising of the penis, which occurs during sexual arousal, though it can also happen in non-sexual situations. Spontaneous erections frequently occur during adolescence due to friction with clothing, a full bladder or large intestine, hormone fluctuations, nervousness, and undressing in a non-sexual situation. It's also normal for erections to occur during sleep and upon waking.

The primary physiological mechanism that brings about erection is the autonomic dilation of arteries supplying blood to the penis, which allows more blood to fill the three spongy erectile tissue chambers in the penis, causing it to lengthen and stiffen. The now-engorged erectile tissue presses against and constricts the veins that carry blood away from the penis. More blood enters than leaves the penis until an equilibrium is reached where an equal volume of blood flows into the dilated arteries and out of the constricted veins; a constant erectile size is achieved at this equilibrium. The scrotum will usually tighten during erection.

What can go wrong with my penis?

As many as one in 10 men suffer from Peyronie’s disease.

Peyronie’s is an often painful scarring or bending of the penis that can make sex uncomfortable or impossible. It involves the growth of fibrous plaque, or harder tissue, in the walls of the penis. A ring of plaque can create an hourglass shape in an erection. A growth on one side can bring on a bend. In severe cases, the bend can be 90 degrees or more.

The condition, which is named after the 18th-century French surgeon who first studied it, tends to affect men in their 40s or older. It is thought to be a response to injury, perhaps during sport or vigorous sex. The trauma, which can go unnoticed at the time, causes the scar tissue to build up. Peyronie’s may also be genetic in some men, while studies have in some cases linked it to low testosterone.

Peyronie’s can cause significant shortening of the penis. Doctors say diagnoses have risen significantly in recent years as men become more comfortable seeking help. Treatment can be complex and uncomfortable – and can require invasive surgery.

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