Human Sexuality

D

Resolution

During resolution, the processes of the excitement and plateau stages reverse, and the bodies of both women and men return to the unaroused state. The muscle contractions that occurred during orgasm lead to a reduction in muscular tension and release of blood from the engorged tissues.

The woman's breasts return to normal size during resolution. As they do, the nipples may appear erect as they stand out more than the surrounding breast tissue. Sex flush may disappear soon after orgasm. The clitoris quickly returns to its normal position and more gradually begins to shrink to its normal size, and the orgasmic platform relaxes and starts to shrink. The ballooning of the vagina subsides and the uterus returns to its normal size. Resolution generally takes from 15 to 30 minutes, but it may take longer, especially if orgasm has not occurred.

In men, erection subsides rapidly and the penis returns to its normal size. The scrotum and testes shrink and return to their unaroused position. Men typically enter a refractory period, during which they are incapable of erection and orgasm. The length of the refractory period depends on the individual. It may last for only a few minutes or for as long as 24 hours, and the length generally increases with age. Women do not appear to have a refractory period and, because of this, women can have multiple orgasms within a short period of time. Some men also experience multiple orgasms. This is sometimes related to the ability to have some orgasms without ejaculation.

V

Sexual Risks

There are a number of pressing sexually related public health and social policy issues facing countries around the world today. According to the United States Centers for Disease Control and Prevention, in the United States a teen becomes pregnant every 30 seconds, and every 13 seconds a teen contracts a sexually transmitted infection (STI). For most people in the United States, engaging in heterosexual intercourse without the use of a condom is the behavior that puts them at greatest risk for infection with human immunodeficiency virus (HIV), which can lead to acquired immunodeficiency syndrome (AIDS) and is often ultimately fatal. Although there is currently no cure for AIDS, there are medications that can help delay the onset of symptoms. Another serious sexually transmitted disease is syphilis, which if left untreated for many years, can lead to paralysis, psychiatric illness, and death. Gonorrhea and chlamydia may produce no obvious symptoms in a woman, but they can lead to sterility if she is not treated. Sexually transmitted diseases should be diagnosed and treated by qualified medical practitioners, and all sexual partners must be treated in order to avoid reinfection.

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Individuals can reduce their exposure to such sexual risks by practicing abstinence, using appropriate methods of contraception to avoid unwanted pregnancies, and using safer sex practices. Such practices include using condoms to avoid exchanging bodily fluids, limiting the number of sexual partners, and restricting sexual behaviors to those with less risk, such as manual stimulation and massage.

VI

Sexual Dysfunctions

Sexual dysfunctions are problems with sexual response that cause distress. Erectile dysfunction (impotence) refers to the inability of a man to have or maintain an erection. Premature ejaculation occurs when a man is not able to postpone or control his ejaculation. Inhibited male orgasm, or retarded ejaculation, occurs when a man cannot have an orgasm despite being highly aroused.

Female orgasmic dysfunction (anorgasmia, or inhibited female orgasm) refers to the inability of a woman to have an orgasm. Orgasmic dysfunction may be primary, meaning that the woman has never experienced an orgasm; secondary, meaning that the woman has had orgasms in the past but cannot have them now; or situational, meaning that she has orgasms in some situations but not in others. Vaginismus refers to a spastic contraction of the outer third of the vagina, a condition that can close the entrance of the vagina, preventing intercourse.

Dyspareunia refers to painful intercourse in either women or men. Low sexual desire is a lack of interest in sexual activity. Discrepant sexual desire refers to a condition in which partners have considerably different levels of sexual interest. These dysfunctions may be caused by physical problems such as fatigue or illness; the use of prescription medications, other drugs, or alcohol; or psychological factors, including learned inhibition of sexual response, anxiety, interfering thoughts, spectatoring (observing and judging one's own sexual performance), lack of communication between partners, insufficient or ineffective sexual stimulation, and relationship conflicts. In such cases, a qualified sex therapist can work with a physician, if necessary, to determine the cause and best treatment options.

VII

Studies of Human Sexuality

Sexuality and lovemaking techniques have been studied in various cultures since ancient times. The Kama Sutra, written in India in the 2nd century bc, is one of the best-known ancient sex manuals. It discusses the spiritual aspects of sexuality and presents many sexual positions and techniques for enhancing enjoyment of intercourse.

In Europe and the United States, the scientific study of human sexuality began in the late 19th century during the Victorian Age, a time of repressive sexual norms. German psychiatrist Richard von Krafft-Ebing focused on what he considered to be the psychopathological problems of sex. Viennese physician Sigmund Freud, founder of psychoanalysis, considered sexuality central to his psychoanalytic theory. Havelock Ellis, an English physician, collected a wealth of information on sexuality from case histories, medical research, and anthropological reports. The first work in his series Studies in the Psychology of Sex was published in 1896. His scientific objectivity foreshadowed modern sexology. Early in the 20th century, German physician Magnus Hirshfeld founded the first sex-research institute in Germany. He conducted the first large-scale sex survey, collecting data from 10,000 men and women. He also initiated the first journal for publishing the results of sex studies, and started a marriage-counseling service. Most of his materials were destroyed by the Nazis during World War II (1939-1945).

In the early 1930s, American anthropologist Margaret Mead and British anthropologist Bronislaw Malinowski began collecting data on sexual behavior in other cultures. The most noted scientific studies of sexuality in the 20th century are those of American biologist Alfred Charles Kinsey and his colleagues and those of William H. Masters and Virginia Johnson. Kinsey began interviewing people about their sexual histories in 1938, and with his colleagues he published Sexual Behavior in the Human Male (1948) and Sexual Behavior in the Human Female (1953), based mostly on interviews with 5,300 white men and 5,940 white women. Masters and Johnson began their clinical studies of the physiology of sexual response and sexual dysfunctions in the 1950s. These observations were published in Human Sexual Response (1966) and Human Sexual Inadequacy (1970), among others. Smaller studies have confirmed many of the findings of these pioneering sex researchers and have challenged certain others. The AIDS crisis has prompted a number of contemporary surveys of sex, including the National Health and Social Life Survey, the results of which were published in the book Sex in America (1994). As in any area of science, particularly relatively new and sensitive areas such as sex research, these studies have been criticized, on the basis of their findings and methodologies, but each study brings us closer to a fuller understanding of human sexuality.

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