Human Sexuality, Fourth Edition

Human Sexuality FOURTH EDITION

SIMON LEVAY • JANICE BALDWIN

Sinauer Associates, Inc. • Publishers Sunderland, Massachusetts U.S.A

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CHAPTER ONE Sexuality: Pathways to Understanding 3 CHAPTER TWO Sex and Evolution 29 CHAPTER THREE Women’s Bodies 59 CHAPTER FOUR Men’s Bodies 87 CHAPTER FIVE Sex Hormones and the Menstrual Cycle 119 CHAPTER SIX Sexual Development 153 CHAPTER SEVEN Gender 191 CHAPTER EIGHT Attraction, Arousal, and Response 219 CHAPTER NINE Sexual Behavior 251 CHAPTER TEN Sexual Relationships 283 CHAPTER ELEVEN Fertility, Pregnancy, and Childbirth 319 CHAPTER TWELVE Contraception and Abortion 357 CHAPTER THIRTEEN Sexuality across the Life Span 399 CHAPTER FOURTEEN Sexual Orientation 447 CHAPTER FIFTEEN Atypical Sexuality 483 CHAPTER SIXTEEN Sexual Disorders 517 CHAPTER SEVENTEEN Sexually Transmitted Diseases 545 CHAPTER EIGHTEEN Sexual Assault, Harassment, and Partner Violence 579 CHAPTER NINETEEN Sex as a Commodity 607

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CHAPTER ONE Sexuality: Pathways to Understanding 3

Why Study Human Sexuality? 3 BOX 1.2 Meet My Dads 15 Sex Research Has Developed from Sociologists focus on the connection between sex Converging Strands 4 and society 16 Observational studies began with Aristotle 4 Sociologists may take an ethnographic approach 18 Sexual ethics have religious roots 5 The economic approach weighs costs and Sex researchers emerged in the late nineteenth benefits 18 century 6 Sex research is becoming a discipline in its own right 19 BOX 1.1 Freud and Hirschfeld: Contrasting Theories on Sexual Orientation 8 Religions Offer Diverse Teachings on Psychological anthropologists investigated non- Sexuality 19 Western perspectives on sex 8 BOX 1.3 Sexual Health for the Millennium 20 Feminists campaigned for sexual reforms 10 Catholicism teaches conservative attitudes toward Biomedical research had a practical impact on people’s sexuality 20 sex lives 11 Protestant teachings are more flexible 21 Sexuality Can Be Studied with a Wide Judaism spans a spectrum 22 Variety of Methods 12 Global religions are embedded in diverse Biomedical research focuses on the underlying societies 22 mechanisms of sex 12 Sex Education Faces Significant Psychologists take diverse approaches to sexuality 13 Obstacles 23

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CHAPTER TWO Sex and Evolution 29

Diverse Methods of Reproduction Have Females often choose among males 43 Evolved 29 Sometimes males make significant investments in Rival Theories Offer Explanations for reproduction 45 Sexual Reproduction 31 BOX 2.3 When Males Get Pregnant 46 BOX 2.1 The Cellular Basis of Reproduction 32 If males invest, sexual selection may work Sexual reproduction may limit harmful mutations 33 differently 46 Sexual reproduction may generate beneficial gene Diverse Relationship Styles Have combinations 34 Evolved 48 Future research may solve the puzzle 35 Social and sexual arrangements are not necessarily the same 48 Why Are There Two Sexes? 35 Male promiscuity offers obvious evolutionary BOX 2.2 The Paradox of Sexless Species 36 benefits 49 Hermaphrodites combine male and female Why are females promiscuous? 49 reproductive functions 37 Female promiscuity leads to adaptive responses Can there be more than two sexes? 38 by males 50 Why are there equal numbers of males and Males may copulate with females by force 51 females? 38 Sometimes, Helping Relatives Reproduce Evolution Has Led to Diverse Methods of Is a Good Strategy 52 Sex Determination 39 Kin selection explains some altruistic animal Sex may be determined by chromosomes 39 behavior 53 Sex may be determined by temperature 40 Sex Has Acquired Other Functions beyond Sexual Selection Produces Anatomical and Reproduction 53 Behavioral Differences between Males BOX 2.4 Does Sexual Morality Have an and Females 41 Evolutionary Basis? The Case of Incest 54 Males and females follow different reproductive Female and male bonobos engage in non- strategies 41 reproductive sex 55 Females and males are exposed to different Bonobos use sex for conflict resolution and alliance reproductive risks 42 formation 56 Males often compete for access to females 42

CHAPTER THREE Women’s Bodies 59

A Woman’s Vulva Includes Her Mons, Cancer can affect the cervix or the endometrium 70 Labia, Vaginal Opening, and Clitoris 59 BOX 3.3 Genital Self-Examination 71 BOX 3.1 Genital Cosmetic Surgery 62 Other uterine conditions include fibroids, There is more to the clitoris than meets the eye 62 endometriosis, abnormal bleeding, and prolapse 73 Should hysterectomy be so common? 74 BOX 3.2 Female Circumcision 64 The appearance of the vaginal opening is variable 65 The Oviducts Are the Site of Fertilization 74 The Vagina Is the Outermost Portion of the Female Reproductive Tract 67 BOX 3.4 Hysteria 75 The G-spot is a controversial erogenous zone 69 The Ovaries Produce Ova and Sex The Anus Can Also Be a Sex Organ 69 Hormones 76 The Uterus Serves a Double Duty 70 The Breasts Have Both Erotic and Reproductive Significance 77

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Breast cancer mortality can be reduced 78 Treatment depends on the diagnostic findings and the Many factors affect the risk of breast cancer 79 woman’s choice 82 Early detection is important 80 Most women with breast cancer return to an active sex life 83 BOX 3.5 Breast Self-Examination 81 BOX 3.6 Is There Sex after Mastectomy? 84

CHAPTER FOUR Men’s Bodies 87

The Male External Genitalia Are the Penis BOX 4.4 Disorders of the Prostate Gland 100 and Scrotum 87 The Nervous System Orchestrates Sexual The penis combines erotic, reproductive, and Arousal 103 excretory functions 88 Erection can be mediated by a spinal reflex 103 BOX 4.1 Male Circumcision 90 BOX 4.5 The Nervous System 104 BOX 4.2 How Big Should a Penis Be? 93 Erectile tissue forms a hydraulic system 107 The scrotum regulates the temperature of Muscles are also involved in erection 109 the testicles 94 The brain influences erection 110 The Testes Produce Sperm and Sex Ejaculation Requires Coordination of Hormones 95 Muscles and Glands 111 BOX 4.3 Disorders of the Testicles 97 Emission is the passage of semen into the urethra 111 Other glands contribute their secretions to Ejaculation is caused by contractions of many muscles the semen 98 in the pelvic floor 112 What is semen? 99 Nudity Is Culturally Regulated 113

CHAPTER FIVE Sex Hormones and the Menstrual Cycle 119

Sex Steroids Consist of Three Groups 119 Other pituitary hormones include prolactin and growth hormone 127 BOX 5.1 Testicles by the Ton—The Discovery of Sex Steroids 121 Protein hormones are secreted by other tissues 128 Testosterone is a sex hormone in both men Prostaglandins and Monoamines Also and women 123 Influence Sexual Functions 128 Estradiol is synthesized from testosterone in A Brain–Pituitary–Testis Feedback Loop both sexes 124 Controls Testicular Function 128 Progesterone is a female hormone 124 The regulation of testosterone levels and Sex steroids activate specific receptor molecules 124 spermatogenesis is coupled 128 Proteins and Peptide Hormones Testosterone and inhibin exert negative feedback on Are Gene Products 125 gonadotropin release 129 Testosterone has multiple functions in men 129 Oxytocin is secreted by neuroendocrine cells of the hypothalamus 125 BOX 5.2 Steroids and Sports 131 GnRH stimulates the release of pituitary sex Estradiol has wide-ranging effects in men’s bodies 132 hormones 125 Menstruation Has Biological and Social The pituitary gonadotropins are follicle-stimulating Aspects 132 hormone (FSH) and luteinizing hormone (LH) 126 BOX 5.3 Attitudes toward Menstruation 133

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Women use pads, tampons, or cups during Sex steroids affect systems in women besides the menstruation 134 reproductive tract 143 The Menstrual Cycle Involves the Ovaries, The menstrual cycle influences sexuality 144 Brain, Pituitary, and Uterus 136 Menstrual Problems Are Common but The cycle is of variable length 136 Treatable 145 The cycle consists of menstrual, follicular, and Menstrual pain might or might not reflect underlying luteal phases 136 pelvic disease 145 BOX 5.4 Menstrual Synchrony: Reality or Premenstrual syndrome has physical and psychological Myth? 137 aspects 146 The menstrual phase is triggered by a drop in Menstruation stops during pregnancy—and for many progesterone levels 137 other reasons 147 The follicular phase is marked by the maturation of Sex Hormone-Related Compounds Exist in ovarian follicles 138 the Environment 148 During the luteal phase the uterus is prepared for BOX 5.5 Sex Hormones in the Environment 149 pregnancy 142

CHAPTER SIX Sexual Development 153

Humans Pass through Distinct Stages of BOX 6.4 Atypical Development: Congenital Development 153 Adrenal Hyperplasia 167 Fertilization Is the Fusion of One Sperm The gonads descend during development 168 with One Ovum 154 BOX 6.5 Atypical Development: 5α-Reductase The conceptus implants in the uterine wall 155 Deficiency 169 During embryonic life, the body plan and organ BOX 6.6 Atypical Development: Hypospadias and systems develop 157 Micropenis 170 Fetal life involves growth and functional Hormones Influence the Sexual maturation 157 Differentiation of the Central Nervous Genetic Sex Is Determined at System 171 Fertilization 158 The CNS contains sexually dimorphic structures 171 Sex is usually determined by the presence or absence Sexual dimorphism arises as a consequence of of the Y-linked gene SRY 159 differing hormonal levels during a sensitive SRY and other genes direct the development of period 172 the gonads 159 Early Hormonal Exposure Influences Later BOX 6.1 Atypical Development: Chromosomal Sexual Behavior 174 Anomalies 160 Experiments on rodents show activational and Sexual Development Involves Growth or organizational effects of androgens 174 Breakdown of Precursor Structures 161 Primates have multiple sensitive periods 175 Primordial germ cells migrate into the developing Other Y-Linked Genes Besides SRY gonads 161 Influence Development 176 BOX 6.2 Atypical Development: Gonadal External Factors Influence Prenatal Sexual Intersexuality 162 Development 177 Male and female reproductive tracts develop from Biological and social factors interact postnatally 177 different precursors 163 Puberty Marks Sexual Maturation 178 BOX 6.3 Atypical Development: Androgen The pubertal growth spurt occurs earlier in girls than Insensitivity Syndrome 164 in boys 178 Male and female external genitalia develop from the Puberty is marked by visible and invisible changes same precursors 165 in the body 179

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What drives puberty? 181 Sex hormones may have organizational effects The body may signal its readiness for puberty at puberty 184 to the brain 182 Intersexuality Raises Complex Social and BOX 6.7 Atypical Development: Precocious and Ethical Issues 185 Delayed Puberty 183 BOX 6.8 My Life With Androgen Insensitivity Dietary changes may be the reason puberty is Syndrome 185 beginning earlier 183

CHAPTER SEVEN Gender 191

Gender Is a Central Aspect of Gender is molded by socialization 202 Personhood 191 Cognitive developmental models focus on thought Gender Research Has Emerged from a processes 205 History of Sexism 192 BOX 7.2 The Boy Who Was Raised as a Girl 206 Gender Identity May Be Discordant with Gender Development Involves Complex Anatomical Sex 193 Interactions 208 Men and Women Differ in a Variety of Transgender People Cross Society’s Cognitive and Personality Traits 193 Deepest Divide 208 Differences in sexuality include attitudes toward casual Transexuals are of more than one kind 209 sex, jealousy, and frequency of masturbation 194 BOX 7.3 Transgenders in Cross-Cultural Many gender differences arise early in life 196 Perspective 210 Biological Factors Influence Gender 197 Changing sex is a multistage process 212 Evolutionary forces act differently on males and females 197 BOX 7.4 How Should We Treat Gender-Dysphoric Children? 214 Experiments demonstrate a role for sex hormones 199 Some transgenders do not want surgery 215 Transgenders and transexuals struggle for awareness BOX 7.1 “Eggs at Twelve” 201 and acceptance 215 Life Experiences Influence Gender 202

CHAPTER EIGHT Attraction, Arousal, and Response 219

Sexual Attraction: It Takes Two 219 Sexual Arousal Has Multiple Roots 232 Beauty is not entirely in the eye of the beholder 220 Fantasy is a common mode of sexual arousal 232 Culture influences the attractiveness of bodies 222 Rape fantasies may be aversive or erotic 234 BOX 8.1 Beauty and Culture 224 Arousal occurs in response to a partner 235 Attractiveness involves senses besides vision 226 Hormones influence sexual arousability 236 Behavior and personality influence sexual Conditioning may influence arousal 237 attractiveness 227 BOX 8.2 Aphrodisiacs and Drugs 238 Familiarity may increase or decrease attraction 228 Sexual Arousal Follows a Response Perceived attractiveness varies around the Cycle 239 menstrual cycle 230 In the excitement phase, genital responses begin 240 Some people do not experience sexual attraction 230 In the plateau phase, arousal is maintained 241 Orgasm is the climax of sexual arousal 242

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BOX 8.3 Female Ejaculation 243 Men experience a refractory period 246 Brain imaging suggests where orgasm may be BOX 8.4 Women and Men Describe Their experienced 244 Orgasms 247 In the resolution phase, arousal subsides 245 The Masters and Johnson cycle may be The phases may be linked in different ways 245 incomplete 247 Some people experience multiple orgasms 246

CHAPTER NINE Sexual Behavior 251

People Derive Pleasure from Diverse Anal Sex May Be a Part of Either Sexual Behaviors 251 Heterosexual or Male Homosexual Masturbation Is a Very Common Form of Behavior 265 Sexual Expression 253 BOX 9.3 The Crime of Sodomy 266 Negative attitudes toward masturbation are still Men and Women May Have Different prevalent 253 Preferences for Sexual Encounters 267 BOX 9.1 The Dreaded M Word 254 Sex Toys Are Used to Enhance Sexual Several demographic factors influence Pleasure 268 masturbation 255 There are Cultural Variations in Sexual Women use more diverse techniques of masturbation Behavior and Attitudes 270 than men 256 The Kama Sutra is the classic work on how to Gay people masturbate more than heterosexuals 256 make love 270 Different cultures have different attitudes toward BOX 9.4 What is “Great Sex”? 271 masturbation 257 The Aka emphasize the importance of The Kiss Represents True Love— frequent sex 272 Sometimes 258 Sexual Touching Takes Many Forms 258 BOX 9.5 Dry Sex 273 Many Disabled People Have Active Sex Oral Sex Is Increasingly Popular 259 Lives 274 Fellatio is oral stimulation of the penis 259 Arthritis is the number one disability affecting sex 274 Cunnilingus is oral stimulation of the vulva 260 Most Sexual Encounters Include BOX 9.6 On Seeing a Sex Surrogate 275 Coitus 261 Spinal cord injuries present a major challenge to sexual expression 276 Coitus can be performed in many different positions 261 Many intellectually disabled people are competent to make sexual choices 278 The man-above position is the traditional favorite 262 BOX 9.2 Progress in Coitus Research 263 The women’s movement encouraged alternative positions 264

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CHAPTER TEN Sexual Relationships 283

Sexual Relationships Are Motivated by One theory proposes that love has three Many Factors 283 components 299 Moral Judgments about Sex Depend on Its BOX 10.4 This Is Your Brain in Love 300 Context 283 Unrequited Love Is Painful for Both BOX 10.1 Who May Marry? 284 Parties 303 Demographic factors affect sexual attitudes 285 Rejection in love damages self-worth 303 Americans’ Attitudes Have Changed over BOX 10.5 Love Stories 304 Time 286 The rejector may experience guilt 305 Attitudes in other countries differ from those in the Life Experiences Mold Our Sexual United States 287 Relationships 305 Casual Sex Has More Appeal to Men than Relationship styles are influenced by childhood to Women 288 attachments 306 BOX 10.2 Getting the BUG 289 Couples in Relationships Resemble Each Hooking up—The new norm? 290 Other 306 Casual sex is more accepted in the gay male Communication Is a Key Factor in the community 292 Success of Relationships 307 Negotiating sex involves flirting 293 Communication may be inhibited by upbringing or Dating Relationships Are Often Short- by the gender barrier 308 Lived 294 Marriage and relationship education teaches communication skills 308 First dates may follow a script 294 How couples deal with conflict affects the stability Same-sex dates have their own scripts 295 of their relationship 309 Dating relationships may evolve rapidly 296 Love, Jealousy, and Infidelity May Be Love Cements Many Sexual Intertwined 311 Relationships 296 Jealousy can have a positive function 311 There are different kinds of love 296 Jealousy can become a high-stakes game 312 Romantic love may be a human universal 296 Extra-Pair Relationships Have Many Styles BOX 10.3 Love in Literature 297 and Motivations 313 Being in love may be the justification for Personal and evolutionary factors influence marriage or sex 298 infidelity 313 People fall in love with attractive persons who show BOX 10.6 We Just Clicked 314 some interest in them 298 Extra-pair relationships are uncommon 315 Researchers are probing the biological basis of love 298

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CHAPTER ELEVEN Fertility, Pregnancy, and Childbirth 319

Pregnancy and Childbirth Raise Major The Second Trimester Is the Easiest 336 Health Concerns 319 Tests can detect fetal abnormalities 337 Pregnancy Is Confirmed by Hormonal BOX 11.4 Choosing Children’s Sex 338 Tests 320 Sex during pregnancy is healthy 339 The Likelihood of Pregnancy Can Be Moderate exercise during pregnancy is beneficial 340 Maximized by Tracking Ovulation 321 The Third Trimester Is a Time of Infertility Can Result from a Problem in the Preparation 340 Woman or in the Man 322 A hospital is the best location for childbirth if A variety of factors can reduce sperm counts 322 complications are foreseen 341 In vitro fertilization can circumvent many sperm Childbirth classes prepare parents for birth 342 problems 322 The fetus also makes preparations for birth 343 BOX 11.1 Are Sperm Counts Declining? 323 Labor Has Three Stages 343 Sperm can be donated 325 Animal studies suggest that the fetus issues the signal Abnormalities of the female reproductive tract may for parturition 343 reduce fertility 326 The first stage of labor is marked by uterine Failure to ovulate can be dealt with by drugs or by contractions and cervical dilation 344 oocyte donation 326 The second stage is the delivery of the baby 345 Surrogate mothers bear a child for someone else 326 The newborn child adapts quickly 346 BOX 11.2 Designer Gametes 327 The third stage is the expulsion of the placenta 347 Adoption is limited by the supply of healthy Premature and delayed births are hazardous 347 infants 328 BOX 11.5 Cesarean Section 348 Fertility declines with age 328 The Period after Birth Places Many Many Embryos Do Not Survive 329 Demands on Parents 349 Rh factor incompatibility can threaten second Postpartum depression may be accompanied by pregnancies 330 disordered thinking 349 Ectopic pregnancy can endanger the Childbirth and parenthood affect sexuality 350 mother’s life 330 Pregnancy Is Conventionally Divided into Breast-Feeding Is the Preferred Method of Three Trimesters 331 Nourishing the Infant 351 Lactation is orchestrated by hormones 351 The fetus secretes sex hormones to sustain pregnancy 331 The content of breast milk changes over time 351 Infant formula is an alternative to breast milk 352 BOX 11.3 Myths of Pregnancy 332 Breast-feeding has many advantages and some Women may experience troublesome symptoms drawbacks 352 during early pregnancy 333 Prenatal care provides health screening, education, Biological Mechanisms May Contribute to and support 333 Maternal Behavior 353 Adequate nutrition is vital to a successful pregnancy 334 Tobacco, alcohol, drugs, and radiation can harm the fetus 335

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CHAPTER TWELVE Contraception and Abortion 357

Birth Control Has a Long History 357 The withdrawal method is simple but challenging 379 Feminists led the campaign to legalize Noncoital sex can be used as a means of avoiding contraception 358 pregnancy 379 Contraception has not yet solved the problem of There Are Contraceptive Options after unwanted births 358 Unprotected Coitus 380 BOX 12.1 Margaret Sanger and the Birth Control Sterilization Is Highly Reliable 381 Movement 359 Vasectomy is a brief outpatient procedure 382 Different users have different contraceptive Tubal sterilization is more invasive and expensive 383 needs 360 Disabled Persons Have Special Physical Methods Block Sperm Contraceptive Needs 385 Transport 361 New Contraceptive Methods Are under Male condoms are reliable when properly used 361 Development 385 Female condoms are relatively intrusive 364 BOX 12.2 Abortion in the United States: Some Key Diaphragms and cervical caps are inconvenient but Statistics 386 have few side effects 365 Several Safe Abortion Procedures Are Spermicides are not very reliable when Available 386 used alone 366 Vacuum aspiration is the standard first-trimester Intrauterine devices require little attention 367 surgical method 387 Hormone-Based Methods Are Easy Dilation and evacuation is used early in the to Use 369 second trimester 387 Combination pills offer health benefits 369 Induced labor and hysterotomy are performed late in Continuous use of combination pills eliminates the second trimester 388 menstrual periods 371 Medical abortions are two-step procedures 388 Progestin-only pills have fewer side effects 372 BOX 12.3 Does Abortion Traumatize Hormones Can Be Administered by Women? 390 Non-Oral Routes 373 Abortions do not cause long-lasting ill-effects 390 Depo-Provera lasts three months 373 Americans Are Divided on Abortion, but Transdermal patches last a week 374 Most Favor Restricted Availability 390 Vaginal rings last three weeks 375 The abortion debate focuses on specific issues 392 Implants are extremely reliable 376 The availability of abortion varies by location 393 Behavioral Methods Can Be Some Countries Use Birth Control to Demanding 376 Regulate Population Growth 395 In fertility awareness methods, couples avoid coitus during the fertile window 377

CHAPTER THIRTEEN Sexuality across the Life Span 399

Some Forms of Childhood Sexual Interpersonal sexual activity can occur during Expression Are Common 399 childhood 402 In contemporary Western culture, children are Cultures vary in their attitudes toward childhood insulated from sex 400 sexuality 403 Some children engage in solitary sexual activity 400 Some Children Have Sexual Contacts with Adults 403 BOX 13.1 Talking with Children about Sex 401

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Most adult–child contacts involve older children Marriage is becoming a minority status 424 and are single encounters 403 Most Married Couples Are Satisfied with Some kinds of adult–child sex are more harmful Their Sex Lives 425 than others 404 Marriage makes sex more satisfying for women 426 Strategies to prevent adult–child sex are quite The frequency of sex declines during marriage 426 effective 405 Preadolescence May Be Marked by an BOX 13.5 Contrast Effects and Marital Woes 427 Increase in Sexual Interest 405 Women’s marital satisfaction declines during middle age 428 BOX 13.2 Sex and Suggestibility 406 Many Factors Bring Relationships to Preadolescent children segregate by sex 406 an End 429 Strict gender norms may traumatize children who Dissimilarity between husbands and wives shortens become gay adults 407 marriages 430 Adolescence Is a Time of Sexual Marital Disruption Can Have Negative and Exploration 408 Positive Consequences 430 Many cultures have puberty rites 408 Divorced men and women can suffer physical, There are social influences on teen sexual psychological, and economic damage 430 behavior 409 Divorce may be the start of a new life 431 Males masturbate more than females 410 Most divorced people remarry 431 The sexual behavior of American teens has increased Does marriage have a future? 432 and diversified 410 Menopause Marks Women’s Transition to BOX 13.3 Losing It 412 Infertility 433 Noncoital sex is popular among teens 412 Menopause may be caused by depletion Teen Sexuality Is Central to Identity of oocytes 434 Development 414 Women may experience a decline in sexual desire Is dating outdated? 414 at menopause 434 Teen pregnancy is declining but is still too Decreased hormone levels affect a woman’s common 415 physiology 434 In Young Adulthood, Conflicting Demands Hormone therapy can reduce menopausal Moderate Sexual Expression 416 symptoms 435 Most young men and women have only a few sex Postmenopausal hormone therapy is partners 417 controversial 436 Cohabitation Is an Increasingly Prevalent There are ethnic differences in the psychological Lifestyle 417 experience of menopause 437 Marriages preceded by cohabitation may be less Men’s Fertility Declines Gradually with durable 418 Age 437 Cohabitation has diverse meanings 419 The Sex Lives of Old People Have Marriage Takes Diverse Forms 420 Traditionally Been Ignored 438 Aging is accompanied by physiological changes in the The formalization of sexual unions has social and sexual response 438 personal functions 420 Medical conditions, drugs, and social factors can BOX 13.4 Mormon Polygamy 420 impair the sexuality of older people 439 Many societies have permitted polygamy 421 Coping strategies may require flexibility 439 Polyamory includes a variety of nonmonogamous Some older people remain sexually active 440 relationships 422 Sex can be highly rewarding for old people 441 The Institution of Marriage Is Evolving 423 BOX 13.6 Sex and Death among Welsh Cheesemakers 442 Companionate marriage makes the availability of divorce a necessity 424

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CHAPTER FOURTEEN Sexual Orientation 447

There Is a Spectrum of Sexual Coming out is a lifelong process 465 Orientations 447 BOX 14.5 Gay Meccas: West Hollywood and Sexual Orientation Is Not an Isolated Northampton 466 Trait 449 Lesbians and gay men are well represented in certain BOX 14.1 Boys Will Be Girls 450 occupations 467 Diverse Theories Attempt to Explain Sexual Gay People Who Belong to Minorities Orientation 451 Have Special Concerns 468 Freud proposed psychodynamic models 451 Gay Sex Has Its Own Style 468 Sexual orientation has been attributed to Some gay people are parents 470 socialization 451 The children of gay parents generally thrive 471 Biological theories focus on prenatal hormones Changing One’s Sexual Orientation is and genes 452 Difficult or Impossible 472 The Basis for Defining Homosexual People Homophobia Has Multiple Roots 472 Has Changed over Time 454 Cultural indoctrination transmits homophobia across Homosexuals were thought of as gender inverts 456 generations 473 Gay people were later subdivided on the basis of Homosexuality is seen as transgressive 474 gender characteristics 456 Overcoming homophobia is a grassroots The Gay Community Has Struggled for enterprise 475 Equal Rights 457 Bisexuals Are Caught between Two The gay rights movement began in Germany 457 Worlds 476 BOX 14.2 Harvey Milk 459 The prevalence of bisexuality depends on definitions 476 BOX 14.3 Gay Marriage in America 460 Bisexuals face prejudice 477 Gay rights are a global issue 460 BOX 14.6 Scenes from Bisexual Life 478 Growing Up Gay Presents Challenges 462 BOX 14.4 Hatred in the Hallways 463

CHAPTER FIFTEEN Atypical Sexuality 483

Sexual Variety Is the Spice of Life 483 Exhibitionists expose themselves to nonconsenting Most fetishisms are related to the body 484 persons 494 People cross-dress for a variety of reasons 486 Voyeurs are aroused by watching others 495 Frotteurism involves surreptitious physical BOX 15.1 Rubber Fetishism and the Internet 487 contact 495 BOX 15.2 Heterosexual Transvestic Fetishism 489 BOX 15.3 Frotteurism on Public Transit 496 Some men are aroused by transgenders 490 Some Adults Are Sexually Aroused by Sadomasochism involves the infliction or receipt of Children 496 pain or degradation 490 Pedophilia and child molestation are not “Adult babies” reenact infancy 491 synonymous 497 Paraphilia Is the Psychiatric Term BOX 15.4 Should Hebephilia be a Paraphilia? 498 for Problematic Sexual Desire or Behavior 492 Attraction may be to girls, boys, or both 499 It is uncertain whether pedophiles have distinctive personalities 499

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Some organizations support “minor-attracted Paraphilias may represent a sexual escape route 508 people” 500 Paraphilias may be facilitated by other psychological A Variety of Other Paraphilias Exist 501 traits 508 Zoophiles are sexually fixated on animals 501 The cycle of abuse may contribute to paraphilias 508 In necrophilia, nonresistance of the partner Theories of Causation Have Suggested a may be arousing 502 Variety of Treatments 509 Sexual violence can be paraphilic 502 Conditioning is intended to change sexual Obscene telephone calling is related to desires 509 exhibitionism 503 Psychotherapy is aimed at preventing repeat offenses 510 BOX 15.5 Autoerotic Asphyxia 504 The efficacy of psychological treatments is Sex Offenders Do Not Necessarily Repeat doubtful 510 Their Offenses 505 Drug treatments interact with neurotransmitters or There Are Numerous Theories of hormones 511 Paraphilia 505 Castration is a treatment of last resort 512 Biological factors may predispose to paraphilia 506 BOX 15.6 Castration: Barbaric Punishment or Paraphilias may result from learning processes 506 Ticket to Freedom? 513 Some paraphilias may represent disorders of courtship 507

CHAPTER SIXTEEN Sexual Disorders 517

Sexual Disorders Are Common 517 There Are Many Reasons for Sexual Pain in Women 530 BOX 16.1 Sensate Focus 518 Men and women’s sexual problems differ 518 BOX 16.3 Dyspareunia: A Case History 531 A multidisciplinary approach to treatment is Vaginismus may make intercourse impossible 532 preferred 519 Difficulty in Reaching Orgasm Is Common BOX 16.2 Kegel Exercises 520 among Women 532 Premature Ejaculation Is Men’s Number Psychotherapy and directed masturbation One Sex Problem 520 may be helpful 533 Faked orgasms offer a questionable solution 534 There are different kinds of premature ejaculation 521 Too Much Interest in Sex Can Cause Drug treatment may be effective 522 Problems 535 Sex therapy may help men to regulate excitation 522 Is excessive sexual behavior an addiction or a compulsion? 536 Delayed Ejaculation Can Be a Side Effect of Several Drugs 524 Compulsive sexual behavior can often be treated with SSRIs 536 Erectile Dysfunction Has Many Causes and Lack of Desire for Sex Is Not Necessarily a Treatments 525 Problem 537 Erectile dysfunction can have physical or Hormone treatment may restore sexual desire 537 psychological causes 525 Simple measures may alleviate the problem 526 BOX 16.4 Sexual Minorities and Sexual Dysfunction 538 Viagra and similar drugs have become the leading treatments 526 Estrogen or androgen treatment may improve sexual desire in women 538 Erectile dysfunction can be treated with devices and implants 527 Sex therapy may be helpful for low sexual desire in women 540 Psychological treatments may be useful 528 New views on women’s response cycles may influence Sexual Pain Is Uncommon in Men 529 treatment options 540 Female Sexual Arousal Disorder Involves Insufficient Genital Response 529 © Sinauer Associates, Inc. This material cannot be copied, reproduced, manufactured or disseminated in any form without express written permission from the publisher.

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CHAPTER SEVENTEEN Sexually Transmitted Diseases 545

Venereal Diseases Were Seen as Recurrent outbreaks are the rule 559 Punishment for Sexual License 545 Drug treatment can shorten or prevent STDs Are Still a Major Problem in the outbreaks 560 United States 546 Herpes is extremely common 560 Lice and Mites Are More of an Annoyance Human Papillomaviruses Can Cause than a Danger 547 Genital Warts—and Cancer 560 Pubic lice itch, and that’s all they do 549 HPV vaccines are available 562 Scabies may be transmitted sexually or Hepatitis Viruses Can Be Sexually nonsexually 549 Transmitted 562 Trichomoniasis Is Caused by a AIDS Is Caused by the Human Protozoan 550 Immunodeficiency Virus 563 Bacterial STDs Can Usually Be Treated with Sexual transmission is chiefly by coitus Antibiotics 551 and anal sex 564 Syphilis Is Down but Not Out 551 BOX 17.2 AIDS in Africa 565 Untreated syphilis progresses through three BOX 17.3 HIV’s Replication Cycle 566 stages 551 HIV infection progresses in a characteristic way 568 Syphilis has resisted elimination 552 AIDS treatment is directed at both the complications Gonorrhea Can Lead to Infertility 552 and the viral replication cycle 569 BOX 17.1 The Tuskegee Syphilis Study 553 There Are Several Ways to Reduce the Chlamydia Causes a Common Infection Likelihood of STD Transmission 571 with Serious Complications 555 Abstinence prevents STDs 571 The Status of Bacterial Vaginosis as an STD Sexually active people can reduce their risk of STDs by Is Uncertain 556 their choice of partners 571 Urethritis Can Be Caused by a Variety of BOX 17.4 Partner Notification 572 Organisms 556 BOX 17.5 Reducing STD Prevalence: Strategies Viral STDs Can Be Dangerous and Hard to That Work 573 Treat 557 Some sexual behaviors are riskier than others Molluscum Contagiosum Is a Self-Limiting for STD transmission 573 Condition 557 Condoms are the mainstay of STD prevention 574 Genital Herpes Is a Lifelong but not Life- Not Everything Is an STD 574 Threatening Infection 558

CHAPTER EIGHTEEN Sexual Assault, Harassment, and Partner Violence 579

What Is Rape? 579 Rape Can Have Severe Ill Effects on the Young women are the most frequent victims Victim 585 of rape 580 Services are available for rape victims 585 Most rapes are not reported 580 BOX 18.2 Reducing the Risk of Rape 586 Most perpetrators are men known to the victim 581 Rape can inflict long-lasting psychological injury 587 College Rapes Are Common 581 BOX 18.3 Ten Ways Young Men Can Prevent BOX 18.1 It Happened to Me 582 Sexual Violence 588 The number one “date rape drug” is alcohol 584 Male victims have special concerns 589

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Rape Laws Have Become More Protective Sexual harassment begins early 597 of Victims 590 Sexual harassment harms its victims 598 Reforms began in the 1970s 590 Victims of sexual harassment can take steps What happens to men who rape? 591 to end it 598 Why Do Men Rape? 591 There Are Three Kinds of Stalkers 599 Rape may have evolutionary roots 592 Intimate Partner Violence Is a Crime with Some characteristics distinguish rapists from Many Names 600 non-rapists 592 Intimate partner violence follows an escalating Social forces influence the likelihood of rape 592 cycle 602 Intervention Programs Are of Uncertain Diverse theories attempt to explain intimate partner Value 593 violence 602 Breaking up is hard to do 603 BOX 18.4 Rape and War 594 Help is available 603 Sexual Harassment Occurs in Many Environments 595 There are two kinds of workplace sexual harassment 596

CHAPTER NINETEEN Sex as a Commodity 607

Can Money Buy You Love? 607 The prostitutes’ rights movement works for Historically, prostitution was viewed as a decriminalization 618 necessary evil 608 The debate on prostitution is worldwide 620 Prostitution is on the decline 608 Juvenile and coerced prostitution are global problems 620 BOX 19.1 Temple Prostitution 609 Phone Sex Blends Prostitution and There Is a Hierarchy of Prostitution 610 Pornography 621 Street prostitution has many risks 610 Pornography Has Always Been Part of Female, male, and transgender streetwalkers have Human Culture 622 different experiences 611 Pornography has battled censorship 622 BOX 19.2 New York City: The Changing Face of New technologies mean new kinds of Prostitution 612 pornography 623 BOX 19.3 Portland, Oregon: Juvenile There is some pornography for women 625 Prostitutes 614 There Are Conflicting Perspectives on the Massage parlors and strip joints are often fronts for Value or Harm of Pornography 626 prostitution 614 Research has not resolved the question of Escort services are the main form of prostitution in the pornography’s effects 627 United States 615 BOX 19.5 Extreme Pornography 628 BOX 19.4 Prostitution: The Dutch Model 616 Underage pornography is widely condemned, but Good Pay Is the Main Motive for common in some countries 629 Prostitution 617 Sex Is Part of the Mass Media 630 Men use prostitutes for many reasons 618 Sex sells, sometimes 631

Glossary G–1 Author Index AI–1 Photo Credits PC–1 Subject Index SI–1 References R–1

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