Sex For Dummies. Dr. Ruth K. Westheimer
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corpus spongiosum, which is under the two corpus cavernosa and surrounds the urethra, is the pipeline for both urine and sperm.
Illustration by Kathryn Born
FIGURE 2-1: The penis: not as simple as it looks!
When a man becomes excited — and I’m not talking about watching his team score the winning touchdown here — the nerves surrounding his penis become active, causing the muscles around the arteries to relax and more blood to flow into the penis. The spongelike material then absorbs the additional blood, making the penis stiff and hard, or erect. This erection tightens the veins so the blood can’t leave the penis, enabling the penis to remain erect. After a man ejaculates or if his arousal fades, detumescence occurs, in which the brain sends a signal to allow the blood to leave the erect penis, and it returns to its flaccid state.
At the base of the penis, the two corpus cavernosa split to form a Y, where the two ends connect to the pubic bone. This ligament controls the angle of the erect penis. I get many questions from men, each asking me if something is wrong with him because the angle of his erect penis isn’t straight out, parallel to the floor. I tell all of them not to go hanging any weights in an effort to change the angle, because they have nothing to worry about!
Penises become erect at all different angles — and the angle doesn’t have any effect on the way the penis performs. As a man gets older, the ligament at the base of his penis stretches, and the angle changes. A man of 70, for example, may have an erection that points downward instead of upward, the way many a young man’s erection does.
At the head of the class: The glans
The head of the penis, called the glans, is shaped like a cone (see Figure 2-2). The opening of the glans is called the meatus (pronounced “me-ate-us”), and at the base of the glans is a crownlike structure called the corona.
Illustration by Kathryn Born
FIGURE 2-2: The glans brings it all to a head.
The glans serves several purposes:
The glans is a little thicker than the rest of the penis, particularly around the corona. This extra thickness serves as a seal to keep the ejaculated semen inside the vagina, near the cervix, after an orgasm. This is nature’s way of making sure that the chances for fertilization are high. The glans also contains the greatest number of nerve endings.
The glans also creates extra friction, which, in this case, produces “good vibrations” that help promote orgasm and ejaculation.
Men aren’t the only ones who benefit from the glans. With all the thrusting of the penis inside the vagina that goes on during intercourse, the woman’s cervix may get damaged if it weren’t for the glans, which acts as a shock absorber.
I suggest that the next time you see your lover’s glans you give it the proper thank you it deserves. I leave the choice of how to do this up to you.
The foreskin: A real cover-up
At birth, the glans is covered by the foreskin, a sheath of skin that opens at the top. In an infant, this opening is very tight and usually can’t be pulled back (or retracted, to use the medical term). Usually, the foreskin loosens up as the baby grows older. When a male has an erection, the foreskin pulls back entirely to fully reveal the glans. The skin of the glans is very sensitive, and the purpose of the foreskin is to protect it.
In the Jewish and Muslim cultures, the foreskin is always surgically removed in a procedure called circumcision. Circumcision has also become popular in many Western societies because the penis is easier to keep clean without the foreskin. Because of today’s better hygiene, some parents and physicians believe that circumcision is no longer necessary, although the debate isn’t entirely over. Figure 2-3 shows the difference in appearance between an uncircumcised and a circumcised penis.
Illustration by Kathryn Born
FIGURE 2-3: The penis on the right is uncircumcised, while the one shown on the left is circumcised.
Small glands underneath the foreskin secrete an oily, lubricating substance. If these secretions accumulate and mix with dead skin cells, a cottage cheese–like substance called smegma forms. In an uncircumcised man, this smegma can build up and lead to infections and, sometimes, even more serious diseases. An uncircumcised man should always take special precautions when bathing to pull back the foreskin and clean carefully around the glans.
Circumcision and sexual performance
Because the skin of the glans of a circumcised male grows tougher and less sensitive than that of an uncircumcised male, people often wonder whether circumcision affects sexual performance.
Some men who aren’t circumcised erroneously believe that, because their skin is more sensitive, they are more likely to have premature ejaculation. I’ve even been asked by adult men if they should be circumcised to cure them of this problem. (Because premature ejaculation is a learned behavior that you can overcome — see Chapter 22 — I don’t recommend having this surgery performed later in life.)
Size and sexual performance
Of course, when considering the penis, what concerns a great many men the most is the size of their sexual organ; they focus on the length and width of the shaft, the main portion of the penis. They think that bigger is better.
Because men are more likely to get turned on by what they see, physical appearance is very important to them. That’s why men are so concerned about penis size — just as some are concerned about the size of women’s breasts. To men, the more there is of a body part that attracts