From Encyclopedia of Sex and Sexuality
The intense feeling of physical pleasure that human beings experience at the climax of sexual stimulation. In the male, orgasm is almost always accompanied by ejaculation, the spurting from the penis of a fluid called semen, which contains spermatozoa, the mobile male seed that, when united with the female egg, begins the process of conception. When the man’s penis is inside the woman’s vagina, the forceful action of orgasm helps push the sperm toward the cervix, the opening to the womb, and to their intended goal, fertilizing the egg. Therefore, the pleasure of male orgasm is directly related to continuation of the species.
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Women also experience orgasm, but the female orgasm is not required for procreation to occur. A woman need not enjoy a sexual episode to become impregnated. In fact, in Victorian times some mothers told their daughters that sex was something only to be endured for the pleasure of the male. On the other hand, the pleasure of the female orgasm, together with the desire to have children, is one of the reasons that women, like men, seek intimacy and fulfilment—so it does play a role in procreation.
The pleasure and sensation of climax that a man feels from orgasm is centered on the male sexual organ. Women report a wider range of orgasmic sensations; many experience an intense climax which may be centered on the clitoris while some report more diffused sensations. In years past, before the development of modern sex research, uncertainty about the nature of women’s orgasms encouraged controversy, instigated in great part by Sigmund Freud, over whether women could experience two different types of orgasm—one clitoral and the other vaginal. Freud postulated that a woman had a clitoral orgasm when her clitoris was directly stimulated and a vaginal orgasm without any stimulation to the clitoris, and that the so-called “vaginal” orgasm was the more intense and more “mature” of the two. Many people today continue to believe that if a woman does not have an orgasm during intercourse brought about by the movement of the penis inside her vagina, she is somehow lacking. We now know that this is not true.
All female orgasms are clitoral orgasms, meaning that it is always the stimulation of the clitoris that triggers the orgasm. For most women the clitoris must come into direct contact with something—a finger, tongue, or vibrator—in order for her to have an orgasm. For about one-third of all women, the movement of the penis inside the vagina creates enough stimulation on the clitoris and the adjacent area to produce an orgasm from intercourse alone. For many other women, prior direct clitoral stimulation can bring orgasm close enough so that the movement of the penis inside the vagina during intercourse then becomes a strong enough trigger. Others can only reach orgasm from direct stimulation, which can take place prior to, during, after, or without intercourse.
Literature and the media have helped spread the idea that there is an “ideal” orgasm, which both partners reach together during intercourse and during which “the earth moves” (actually, it was the writer Ernest Hemingway who coined the phrase in his 1940 novel, For Whom the Bell Tolls). Many couples become frustrated with their sex lives because they cannot attain this goal. While such simultaneous intensity is not a myth, it is a rare enough occurrence to be something that should not be sought directly, but instead enjoyed if it happens. Instead, couples should learn to appreciate sexual satisfaction by whatever means it takes them to achieve it. Orgasms are not all alike, but each is pleasurable in its own way.
The male orgasm is usually strongest in younger men. As a man grows older, the strength at which the semen is ejaculated diminishes, as does the intensity of the orgasmic experience. (As they grow older, men also require a longer time to obtain an erection after an orgasm.) This time necessary for orgasmic response to occur in a man can be very short. Sometimes this time period is too short, a condition called premature ejaculation. This condition is not physical; it is often a conditioned or psychological disability that can be changed so that the man can, to a greater extent, gain control over the timing of his orgasm. Either because of a physical problem or because of intense training, a man’s orgasms may appear not to be accompanied by ejaculation.
The sexual response cycle is similar in men and women, though women differ in their capacities to have multiple orgasms and their overall response time is usually slower than that of males. There are four stages to the cycle. The first is called the excitement stage, in which the body begins to react to sexual stimuli. These can be anything: a sight, a sound, an odor, a touch, or just a memory of a past experience. In the male it begins with an erection, while in females the first reaction is lubrication of the vagina, which results from engorgement of the vaginal blood vessels.
If the stimuli continue, excitement increases and the next stage, called the plateau stage, is reached. The name comes from the fact that this stage can continue for a long or short time, depending on the desire of the people involved. During this stage, blood trapped in the sex organs of both sexes causes a pleasurable swelling.
The orgasmic stage is reached when the male or female has reached a high degree of sexual tension, triggering an orgasm and a series of muscular contractions in or near the sex organs. According to research done by Masters and Johnson, there may be from six to fifteen contractions, each lasting for about a second in the male and occurring more rapidly—often as a “fluttering”—in the female. In the male the mind perceives the orgasm as taking place in the penis, the prostate gland, and the seminal vesicles, while in the female the mind perceives it as taking place in the muscles and tissues around the clitoris and in the vagina and uterus. In both sexes, though it is often more pronounced in the female, the whole body can also be involved, often with spasmodic contractions of the limbs, fingers, toes, or face. Some women are multi-orgasmic and may experience many orgasms before achieving complete satisfaction.
In males, the resolution phase comes immediately after orgasm, as the body relaxes and breathing and blood pressure return to normal. There follows a refractory period, during which a man cannot have a new erection. In young men this period can be only a few minutes, while in older men it can last for several days. The resolution phase is longer in women, who bask in what is called the afterglow. During this period they seek continued physical intimacy to fully experience sexual satisfaction. However, women’s refractory periods are shorter than men’s, permitting some of them to experience multiple orgasms some of the time.
While most men do not have any difficulties experiencing orgasms, the same is not true of all women. For many years the term frigid was applied to women who were not orgasmic, but that has been replaced with the word preorgasmic, because in most cases these women can be taught how to have orgasms, usually by teaching them to masturbate.