FEMALE ORGASM:

After a woman becomes sexually aroused, her heart beats faster while her breathing quickens. Often, she'll tighten various muscles all over her body. Her breasts usually enlarge somewhat, the nipples tend to stand out while the areolas become noticeably enlarged. Some women flush red on their face, neck and chest. The visible part of the clitoris also swells slightly.

Secretions occur inside and at the opening of the vagina. Her labia flatten and open. The vagina lengthens and widens internally, changing what was a potential space into more of an actual space . These vaginal changes are mainly a result of a rush of blood to the pelvic area -- called engorgement -- which provides a generally pleasurable warmth in a female's genital area.

As her arousal increases, so does engorgement as well as most of the changes mentioned above becoming more pronounced. The one area that doesn't follow this pattern is the clitoris. Instead of continually swelling, it actually begins to retract under the clitoral hood and decreases in length by about 50%. This is a sign that orgasm is imminent for most women, as long as optimal stimulation continues.

The orgasm itself begins with strong muscle contractions. These contractions can be finished within four seconds or last up to about 15 seconds. They tend to occur at intervals of 0.8 seconds. Also, the inner two-thirds of the vagina usually open up even more, while the uterus contracts.

During orgasm, skin flushing generally reaches its maximum. Muscles may keep contracting, while blood pressure, heart rate and respiratory rate continue to rise. Some women make sounds reflecting the pleasure they are experiencing.

Signs confirming orgasm

Rhythmic muscle contractions occur in the outer third of the vagina , the uterus and anus . The first muscle contractions are the most intense, and occur at a rate of about 1 per second. As the orgasm continues, the contractions become less intense and occur at a more random rate.

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  A mild orgasm may have 3 -5 contractions, an intense orgasm 10 -15 .
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  The "sex flush" (redness) becomes even more pronounced and may cover a greater percentage of the body.
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  Muscles throughout the body may contract during orgasm, not just those in the pelvic area.
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  Some women will emit or spray some fluid from their urethra during orgasm. This is often called female ejaculation.
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  A woman's facial expression may indicate that she is in pain when she is having a pleasurable orgasm.
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  At the peak of orgasm the entire body may become momentarily rigid.
  

MALE ORGASM:

Ejaculation and the Male Orgasm
The male orgasm is not just about ejaculation. It is possible to have an orgasm without ejaculation.

• Pre-adolescent boys may experience an orgasm without ejaculation.
• Some men do not have an ejaculation until several seconds after orgasm.
• Some men, who are incapable of ejaculation, are still capable of orgasm.
• Some men, may experience several ejaculations and go on to have further orgasms, but without ejaculation.

Physical Experience of the Male orgasm
The male orgasm seems to have psychological as well as a physical effects. Some men say that they have a more focal experience, feeling the orgasm in the scrotum and the genital area. Other men report their orgasm as a feeling that spreads over to some parts of the body and others that their orgasm is felt all over. How much of this is physical and how much psychological is difficult to judge.

What Happens During the Male Orgasm?
During the male sex act a man's pelvic thrusts become less voluntary and other muscles of the body begin to contract rhythmically. As the orgasm begins, heart rate, blood pressure and respiration all increase.