men become sexually aroused, hormones, muscles,nerves,
and blood vessels all work with one another tocreate an
erection. Nerve signals, sent from the brain to the penis, stimulate muscles to relax. This, in turn, allows blood to flow to the tissue in the penis. Once the blood fills the penis and an erection is achieved, the blood vessels to
the penis close off so that the erection is maintained.

Following sexual arousal, the veins to the penis again open
up, allowing the blood to leave.

At some point in a man’s life, he may have difficulty achieving or maintaining an erection. Erection problems occur when you can’t achieve or maintain an erection that’s firm enough to have sexual intercourse.

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