Orgasms vary from person to person, but they all have one thing in common: They are sudden, pleasurable discharges of sexual tension that result in muscular contractions in the genital region. The effects are felt throughout the entire body as muscles contract, heart rate speeds up, brain wave patterns shift, and pupils dilate.

Although the end result is pretty similar, men and women are stimulated in different ways. In men, stimulation of nerve endings on the penis—particularly the glans, or tip—leads to ejaculation. During orgasm, nerves going to the prostate trigger the ejaculation. This feeling of enjoyment, say evolutionary biologists, is a built-in reward system that promotes human reproduction. (However, it is possible for a man to have an orgasm without ejaculation, and ejaculation may occur without orgasm by direct stimulation of the prostatic nerves.)

In women, stimulation of nerves in the clitoris, the nipples, and possibly the labia minora and the G-spot (an area on the front wall of the vagina that’s the female prostate gland) builds up to orgasm. Signals are transmitted to an area of the brain called the hypothalamus, which then secretes a hormone called oxytocin. It’s spread to the blood, brain, and spinal cord, triggering those pleasurable feelings and muscle contractions. Unlike in men, female orgasms don’t play a role in reproduction. This may explain why some 30 percent of women report rarely experiencing an orgasm during sex. However, it’s physically possible for women to experience more than one orgasm during sexual intercourse. In both men and women, the brain participates, and the orgasm is often described as a reflex.

Along with the enjoyable effects, orgasms may also help protect health. Studies show that orgasms can lower stress levels, improve sleep quality, and, in men, reduce the risk of prostate cancer.

ADDITIONAL FACTS

  1. A woman named Xaviera Hollander (1943–), author of The Happy Hooker, reportedly experienced an orgasm when a police officer placed a hand on her shoulder.
  2.   In French, orgasms are described as la petite mort, or “the little death.”
  3. Until the 1930s, doctors stimulated orgasms in women to treat “hysteria.” This clinical procedure was called a medical massage.