An orgasm, also known as a climax, is a pleasurable physiological, and to no small degree a psychological, response to sexual stimulation, that can be experienced by both males and females. The orgasm is one of nature's ways of making certain that an animal will engage in sexual intercourse, thus propagating its own genes.

Table of contents
1 General
2 Human male orgasm
3 Human female orgasm
4 Orgasm in non-human species
5 See also
6 External links

General

Orgasm is the third stage of four in the currently accepted model of the physiological process of sexual stimuation. It is the conclusion of the plateau phase in a release of sexual tension. Both males and females experience quick cycles of muscle contraction of the anus and lower pelvic muscles, as well as in the sexual organs.

Human male orgasm

In a human male orgasm, there are rapid, rhythmic contractions of the prostate, urethra and the muscles at the base of the penis, which force stored semen to be expelled through the penis's urethral opening. This is referred to as ejaculation. The process usually takes from 3 to 10 seconds. The process is usually, but not always, extremely pleasurable. Note that it is possible to ejaculate without reaching orgasm, and to have an orgasm without ejaculation (opening the door for male multiple orgasms). Following orgasm, a refractory period occurs during which a man cannot have another orgasm. This period can be anywhere from less than a minute to over half a day, depending on such factors as the individual and his age.

Human female orgasm

In a human female orgasm, orgasm is preceded by moistening of the vaginal walls, and an enlargement of the clitoris due to increased blood flow trapped in the clitoris's spongy tissue. Some women exhibit a sex flush; a reddening of the skin over much of the body due to increased blood flow to the skin. As a woman comes closer to having orgasm, the clitoris moves inward under the clitoral hood, and the labia minora (minor lips) become a darker pink. As orgasm becomes imminent, the vagina decreases in size by about 30% and also becomes congested with blood. The uterus then experiences muscular contractions. A woman experiences full orgasm when her uterus, vagina and pelvic muscles undergo a series of rhythmic contractions.

After the orgasm is over, the clitoris re-emerges from under the clitoral hood, and returns to its normal size in less than 10 minutes. Unlike men, women do not have a refractory period, and thus can experience a second orgasm soon after the first; some women can even follow this with a third, or even fourth orgasm; this is known as multiple orgasms. Research shows that about 13% of women experience multiple orgasms; a larger number may be able to experience this with the proper stimulation (such as a vibrator) and frame of mind.

Orgasms in both men and women are often associated with other involuntary actions, including vocalizations and muscular spasms in other areas of the body. Also, a generally euphoric sensation is associated with orgasm.

Female ejaculation

Many women experience an expulsion of fluid during orgasm. In many cases the origin of this fluid is the Skene's glands. For further details, see female ejaculation.

Vaginal vs. clitoral orgasms

A distinction is sometimes made between clitoral and vaginal orgasms in women. Many doctors and feminist advocates have claimed that vaginal orgasms do not exist, and that female orgasms are obtained only from clitoral arousal. Recent discoveries about the size of the clitoris -- it extends inside the body, around the vagina -- would seem to support this theory. On the other hand, other sources argue that vaginal orgasms are dominant or more "mature."

This latter viewpoint was first promulated by Freud. In 1905, Freud argued that clitoral orgasm was an adolescent phenomenon, and upon reaching puberty the proper response of mature women changes to vaginal orgasms. [1] While Freud did not provide evidence supporting this basic assumption, the consequences of the theory were greatly elaborated thereafter.

In the 1966, Masters and Johnson published pivotal research into the phases of sexual stimulation. Their work included women as well as men, and unlike Kinsey previoiusly (in 1948 and 1953), set out to determine the physiological stages leading up to and following orgasm. [1] One of the results was the promotion of the idea that vaginal and clitoral orgasms follow the same stages of physical response. Additionally, Masters and Johnson argued that clitoral stimulation is the primary source of orgasms.

This standpoint has been adopted feminist advocates, to the extent that some hold that the vaginal orgasm was a mirage, created by men for their convenience. Certainly many women can only experience orgasm with clitoral stimulation, either alone or in addition to vaginal stimulation, while (less commonly) other women can only experience orgasm with vaginal stimulation. The clitoral-only orgasm school of thought became an article of faith in some feminist circles. Alternatively, some feminists instead feel the clitoral orgasm robs females of the source of the womanhood.

A new understanding of vaginal orgasm has been emerging since the 1980s. Many women report that some form of vaginal stimulation is essential to subjectively experience a complete orgasm, in addition to or in lieu of external (clitoral) stimulation. Recent anatomical research has pointed towards a connection between intravaginal tissues and nerve endings on one hand, and the clitoris on the other. This, combined with the anatomical evidence that the internal part of the clitoris is a much larger organ than previously thought could also explain credible reports of orgasms in women who have undergone clitoridectomy as part of so-called female circumcision.

Orgasm in non-human species

to be written

See also

External links