葛特马赫研究所(英语:Guttmacher Institute)指出,在2002年,6200万名年龄介乎15-44岁的女性当中,就有62%至少采用一种避孕方法去避孕。在当时的美国,最普遍的避孕方法为服用避孕药(30.6%),其次为输卵管结扎(27.0%)以及使用男用避孕套(18.0%),27%使用避孕用品的青少年女性则以避孕套为首选[113]。2014年,一份由凯泽家庭基金会(英语:Kaiser Family Foundation)发表的报告指出,在性活跃的美国青少年(年龄介乎15-19岁)当中,就有53%女性及66%男性报称在上一次性交当中有使用避孕套;22.4%的青少年女性每日服用避孕药去避孕[114]。
“性交”一词通常指的是阴茎-阴道交[2][27]。研究表明,绝大多数异性伴侣几乎每次发生性行为时都会进行阴道交[27]。美国性健康与行为调查在2010年指出阴道交是“最普遍的性行为,无分年龄、性别和种族[27]。”克林特·布鲁斯(Clint E. Bruess)等人于2013年指出它是“一种最常被人研究的行为”,并表示在不同文化中,当人们提到“性行为”或“性交”时,往往是指“青少年性教育课程的重心[116]。”韦腾(Weiten)等人指出性交是“在我们的社会中广泛地受到认可和进行的性行为[52]。”
此外研究者已对不同文化中性交的盛行率进行比较。2003年,法国国家人口统计研究院(英语:Institut national d'études démographiques)进行一项名为《什么时候男性和女性才会发生第一次性交?》(At what age do women and men have their first sexual intercourse?)的跨文化研究。其首先研究撒哈拉沙漠以南的非洲地区(马里、塞内加尔和埃塞俄比亚)。数据表明,身处这些社会的男性的性启蒙晚于女性,但通常发生于婚外。该研究认为印度次大陆也包括在以上群体中,尽管相关数据只从尼泊尔取得[117][118]。
1995年,美国的全国调查显示,美国有至少3/4的男女在青少年晚期中进行过性交,超过2/3拥有性经验的青少年有两个或以上的性伴侣[119]。据美国卫生及公共服务部发表的《2002年家庭增长的全国调查》(2002 National Survey of Family Growth),15-44岁的受访者平均首次性交年龄分别为17.3岁(女性)和17.0岁(男性)[120][121][122]。美国国家卫生统计中心(英语:National Center for Health Statistics)的特别表列显示,2011年至2013年此一数字进一步下降至17.2岁(不论男女)[123]。美国疾病控制与预防中心指出在2011-2013年,44.1%的女性和46.8%的男性在19岁或以前从事过至少一次性交[124];43%美国未婚青少年女性及45.7%美国未婚青少年男性有从事过性交[125]。中心还指出美国女性更多与比她们大1-3岁的男性发生首次性行为[126]。
一些在20世纪70年代至90年代进行的研究显示,对于青少年而言,性交跟自尊是有关系的[205],但是其他在20世纪80年代至90年代进行的研究则表示,性交跟自尊在总体上只有很少关系,或根本没有关系[206]。到了90年代,证据一般都是支持后者[206],更进一步的研究亦同样指出性交跟自尊只有很少关系,或根本没有关系[207][208]。丽莎·阿雷(Lisa Arai)这名学者指出:“‘较早的性活动和怀孕跟自尊过低有关’的观念在20世纪后半叶开始进入主流,特别是美国……一份关于自尊与青少年性行为、性态度、性意愿之间的关系的系统评价发现,62%的行为调查和72%的态度调查显示两者毫无统计学意义(Goodson et al,2006)[208]。”但亦有研究发现不是童贞的少男的自尊心高于还是童贞的;自我意象差且自尊心低的青少女更倾向于从事高风险行为,比如无进行任何保护的性行为、拥有多个性伙伴[205][207][208] 。
另一项关于“同意”与否的性事就是动物恋,指的一般是人与动物之间所发生的性行为,但亦可指对相关实践的执着,属性偏离的一种[230][231][232]。在某些司法管辖区,某人与非人动物发生性行为不属违法,但在其他地区,则会遭视为违反虐待动物法,或是干犯了违反自然罪(英语:crime against nature)[233]。支持订立相关法律的人所提出的理由包括“兽交对动物是有害的”[234]、“动物无法表达同意与否”[234]、“[兽交]有违人的基本尊严”[235]。反对订立者所提出的理由则包括“人类既然可以杀死动物并吃之,那么禁止人兽交已在逻辑上说不通”[236]、“吃动物也侵犯了人及动物的尊严”[237]、“动物可以某些方式表达同意”[238]。
依据某些地区的离婚法,可以以拒绝与配偶进行性交为由申请离婚,并视作“因抛弃对方而离婚”(grounds of abandonment)[250]。詹姆斯·德维尔(James G. Dwyer)在他的著作中指出设有无过错离婚(英语:no-fault divorce)法能使“女性更轻易地从婚姻关系中脱离,并使妻子在婚姻中得到更多的控制权……这是‘丈夫强奸妻子’的相关法律观念改变所致[240]。”
威卡教信徒的相关看法就如威卡教经典《女神的诫命(英语:Charge of the Goddess)》中所写的般:“让欢乐的心中充满对我[女神]的崇拜,因为一切爱与快乐的行为才是属于我的仪式。”此一段似乎在暗示威卡教的女神充许人们自由地探索肉欲和愉悦感。亦段亦已跟《巫士守则(英语:Wiccan Rede)》的最终格言混合:“威卡教的教规八字真言是,‘为所欲为伤人不为’[278]。”威卡教鼓励人们对他们的性接触负责,不论其种类[279]。
Wayne Weiten; Margaret A. Lloyd; Dana S. Dunn; Elizabeth Yost Hammer. Psychology Applied to Modern Life: Adjustment in the 21st Century. Cengage Learning. 2008: 422–423 [2012-01-05]. ISBN 0495553395. (原始内容存档于2013-12-31). Vaginal intercourse, known more technically as coitus, involves inserting the penis into the vagina and (typically) pelvic thrusting. ... The man-above, or "missionary," position is the most common sex position.
Sandra Alters; Wendy Schiff. Essential Concepts for Healthy Living. Jones & Bartlett Publishers. 2012: 180–181 [2013-08-31]. ISBN 1449630626. (原始内容存档于2013-12-31). Most heterosexuals are familiar with the notion of 'having sex' or sexual intercourse as vaginal sex, the insertion of a penis into a vagina. Vaginal sex, or coitus, is the most common and popular form of intimate sexual activity between partners.
Sexual intercourse most commonly means penile–vaginal penetration for sexual pleasure and/or sexual reproduction; dictionary sources state that it especially means this, and scholarly sources over the years agree. See, for example;
Richard M. Lerner; Laurence Steinberg. Handbook of Adolescent Psychology. John Wiley & Sons. 2004: 193–196 [2013-04-29]. ISBN 0471690449. (原始内容存档于2013-10-15). When researchers use the term sex, they nearly always mean sexual intercourse – more specifically, penile–vaginal intercourse... The widespread, unquestioned equation of penile–vaginal intercourse with sex reflects a failure to examine systematically 'whether the respondent's understanding of the question matches what the researcher had in mind.'
Fedwa Malti-Douglas. Encyclopedia of Sex and Gender: A-C. Macmillan Reference. 2007: 308. ISBN 0028659619. Sexual intercourse. [T]he term coitus indicates a specific act of sexual intercourse that also is known as coition or copulation. This 'coming together' is generally understood in heteronormative terms as the penetration of a woman's vagina by a man's penis.
Irving B. Weiner; W. Edward Craighead. The Corsini Encyclopedia of Psychology4. John Wiley & Sons. 2010: 1577 [2013-08-21]. ISBN 0470170239. (原始内容存档于2013-12-31). Human sexual intercourse, or coitus, is one of the most common sexual outlets among adults. Sexual intercourse generally refers to penile penetration of the vagina...
Clint E. Bruess; Elizabeth Schroeder. Sexuality Education Theory and Practice. Jones & Bartlett Publishers. 2013: 152 [2014-12-05]. ISBN 1449649289. (原始内容存档于2015-03-26). Vaginal sex is defined as when a penis or sex toy is inserted into a vagina for pleasure. In many cultures around the world, vaginal sex is what is usually implied when people refer to 'having sex' or 'sexual intercourse.' It is the most frequently studied behavior and is often the focus of sexuality education programming for youth.
Richard M. Lerner; Laurence Steinberg. Handbook of Adolescent Psychology. John Wiley & Sons. 2004: 193–196 [2013-04-29]. ISBN 0471690449. (原始内容存档于2013-10-15). When researchers use the term sex, they nearly always mean sexual intercourse – more specifically, penile–vaginal intercourse... The widespread, unquestioned equation of penile–vaginal intercourse with sex reflects a failure to examine systematically 'whether the respondent's understanding of the question matches what the researcher had in mind.'
Nancy W. Denney; David Quadagno. Human Sexuality. Mosby-Year Book. 2008: 273. ISBN 0801663741. Although the term intercourse is usually used to refer to the insertion of the penis into the vagina, it is also used to refer to oral intercourse or anal intercourse in which the penis is inserted into the mouth or the anus, respectively.
Randall, H. E. & Byers, S. E. What is sex? Students' definitions of having sex, sexual partner, and unfaithful sexual behaviour. The Canadian Journal of Human Sexuality. 2003, 12: 87–96. Recently, researchers in the United States, the United Kingdom, and Australia have investigated university students' definitions of having sex. These studies found that students differ in their opinions of what sexual behaviours constitute having sex (Pitts & Rahman, 2001; Richters & Song, 1999; Sanders & Reinisch, 1999). While the vast majority of respondents (more than 97%) in these three studies included penile–vaginal intercourse in their definition of sex, fewer (between 70% and 90%) respondents considered penile–anal intercourse to constitute having sex. Oral-genital behaviours were defined as sex by between 32% and 58% of respondents.
Bryan Strong; Christine DeVault; Theodore F. Cohen. The Marriage and Family Experience: Intimate Relationship in a Changing Society. Cengage Learning. 2010: 186 [2011-10-08]. ISBN 0-534-62425-1. Most people agree that we maintain virginity as long as we refrain from sexual (vaginal) intercourse. But occasionally we hear people speak of 'technical virginity' [...] Data indicate that 'a very significant proportion of teens ha[ve] had experience with oral sex, even if they haven't had sexual intercourse, and may think of themselves as virgins' [...] Other research, especially research looking into virginity loss, reports that 35% of virgins, defined as people who have never engaged in vaginal intercourse, have nonetheless engaged in one or more other forms of heterosexual sexual activity (e.g., oral sex, anal sex, or mutual masturbation).
Fedwa Malti-Douglas. Encyclopedia of Sex and Gender: A-C. Macmillan Reference. 2007: 308. ISBN 0028659619. Sexual intercourse. [T]he term coitus indicates a specific act of sexual intercourse that also is known as coition or copulation. This 'coming together' is generally understood in heteronormative terms as the penetration of a woman's vagina by a man's penis.
Copulation. Dorland's Medical Dictionary for Health Consumers, 2007/TheFreeDictionary.com for various dictionary definitions. [2012-09-06]. (原始内容存档于2012-08-10).
*Ken Plummer. Modern Homosexualities: Fragments of Lesbian and Gay Experiences. Routledge. 2002: 187–191 [2013-08-24]. ISBN 1134922426. (原始内容存档于2014-07-08). [S]ome sexual practices are regarded as inherently better (normal, natural, more satisfying) than others, with vaginal intercourse privileged as the 'Real Thing.' Such beliefs, influenced by views about sex as ultimately a reproductive function, continue to be perpetuated through discourses on sex despite a number of important contradictions.
Richard M. Lerner; Laurence Steinberg. Handbook of Adolescent Psychology. John Wiley & Sons. 2004: 193–196 [2013-04-29]. ISBN 0471690449. (原始内容存档于2013-10-15). When researchers use the term sex, they nearly always mean sexual intercourse – more specifically, penile–vaginal intercourse... The widespread, unquestioned equation of penile–vaginal intercourse with sex reflects a failure to examine systematically 'whether the respondent's understanding of the question matches what the researcher had in mind.'
Fedwa Malti-Douglas. Encyclopedia of Sex and Gender: A-C. Macmillan Reference. 2007: 308. ISBN 0028659619. Sexual intercourse. [T]he term coitus indicates a specific act of sexual intercourse that also is known as coition or copulation. This 'coming together' is generally understood in heteronormative terms as the penetration of a woman's vagina by a man's penis.
Irving B. Weiner; W. Edward Craighead. The Corsini Encyclopedia of Psychology4. John Wiley & Sons. 2010: 1577 [2013-08-21]. ISBN 0470170239. (原始内容存档于2013-12-31). Human sexual intercourse, or coitus, is one of the most common sexual outlets among adults. Sexual intercourse generally refers to penile penetration of the vagina...
Clint E. Bruess; Elizabeth Schroeder. Sexuality Education Theory and Practice. Jones & Bartlett Publishers. 2013: 152 [2014-12-05]. ISBN 1449649289. (原始内容存档于2015-03-26). Vaginal sex is defined as when a penis or sex toy is inserted into a vagina for pleasure. In many cultures around the world, vaginal sex is what is usually implied when people refer to 'having sex' or 'sexual intercourse'. It is the most frequently studied behavior and is often the focus of sexuality education programming for youth.
Nancy W. Denney; David Quadagno. Human Sexuality. Mosby-Year Book. 2008: 273. ISBN 0801663741. Although the term intercourse is usually used to refer to the insertion of the penis into the vagina, it is also used to refer to oral intercourse or anal intercourse in which the penis is inserted into the mouth or the anus, respectively.
*Ken Plummer. Modern Homosexualities: Fragments of Lesbian and Gay Experiences. Routledge. 2002: 187–191 [2013-08-24]. ISBN 1134922426. (原始内容存档于2015-03-26). The social construction of 'sex' as vaginal intercourse affects how other forms of sexual activity are evaluated as sexually satisfying or arousing; in some cases whether an activity is seen as a sexual act at all. For example, unless a woman has been penetrated by a man's penis she is still technically a virgin even if she has had lots of sexual experience.
Randall, H. E. & Byers, S. E. What is sex? Students' definitions of having sex, sexual partner, and unfaithful sexual behaviour. The Canadian Journal of Human Sexuality. 2003, 12: 87–96. Recently, researchers in the United States, the United Kingdom, and Australia have investigated university students' definitions of having sex. These studies found that students differ in their opinions of what sexual behaviours constitute having sex (Pitts & Rahman, 2001; Richters & Song, 1999; Sanders & Reinisch, 1999). While the vast majority of respondents (more than 97%) in these three studies included penile–vaginal intercourse in their definition of sex, fewer (between 70% and 90%) respondents considered penile-anal intercourse to constitute having sex. Oral-genital behaviours were defined as sex by between 32% and 58% of respondents.
Bryan Strong; Christine DeVault; Theodore F. Cohen. The Marriage and Family Experience: Intimate Relationship in a Changing Society. Cengage Learning. 2010: 186 [2011-10-08]. ISBN 0-534-62425-1. Most people agree that we maintain virginity as long as we refrain from sexual (vaginal) intercourse. ...But occasionally we hear people speak of 'technical virginity' ... Other research, especially research looking into virginity loss, reports that 35% of virgins, defined as people who have never engaged in vaginal intercourse, have nonetheless engaged in one or more other forms of heterosexual activity (e.g. oral sex, anal sex, or mutual masturbation). ... Data indicate that 'a very significant proportion of teens ha[ve] had experience with oral sex, even if they haven't had sexual intercourse, and may think of themselves as virgins'.
Robert Crooks; Karla Baur. Our Sexuality. Cengage Learning. 2010: 286–289 [2012-08-30]. ISBN 0495812943. Noncoital forms of sexual intimacy, which have been called outercourse, can be a viable form of birth control. Outercourse includes all avenues of sexual intimacy other than penile–vaginal intercourse, including kissing, touching, mutual masturbation, and oral and anal sex.
*Richard D. McAnulty; M. Michele Burnette. Exploring Human Sexuality: Making Healthy Decisions. Allyn & Bacon. 2003: 229. ISBN 020538059X. 9780763741488.
Richard M. Lerner; Laurence Steinberg. Handbook of Adolescent Psychology. John Wiley & Sons. 2004: 193–196 [2013-04-29]. ISBN 0471690449. (原始内容存档于2013-10-15). When researchers use the term sex, they nearly always mean sexual intercourse – more specifically, penile–vaginal intercourse... The widespread, unquestioned equation of penile–vaginal intercourse with sex reflects a failure to examine systematically 'whether the respondent's understanding of the question matches what the researcher had in mind.'
Ken Plummer. Modern Homosexualities: Fragments of Lesbian and Gay Experiences. Routledge. 2002: 187–191 [2013-08-24]. ISBN 1134922426. (原始内容存档于2015-03-18). [S]ome sexual practices are regarded as inherently better (normal, natural, more satisfying) than others, with vaginal intercourse privileged as the 'Real Thing.' Such beliefs, influenced by views about sex as ultimately a reproductive function, continue to be perpetuated through discourses on sex despite a number of important contradictions.
Arthur G. Miller. Perspectives on Evil and Violence. Psychology Press. 1999: 240 [2013-04-29]. ISBN 0805897844. (原始内容存档于2014-01-08). Many people consider penile–vaginal intercourse the only form of 'real' sex.
Jonathan Engel. The Epidemic: A History of Aids. HarperCollins. 2009: 242 [2013-08-30]. ISBN 0061856762. (原始内容存档于2013-12-31). Many men simply did not like the feel of condoms, or associated them with emasculation. They say, 'Unless it's flesh on flesh, it's not real sex...
Pfaus JG, Flanagan-Cato LM, Blaustein JD. Female sexual behavior. Plant T, Zeleznik A, et al (编). Physiology of Reproduction 4th. Academic Press. 2015.
Nei, M.; Niimura, Y.; Nozawa, M. The evolution of animal chemosensory receptor gene repertoires: roles of chance and necessity. Nat. Rev. Genet. 2008, 9 (12): 951–963.
Zhang, J.; Webb, D.M. Evolutionary deterioration of the vomeronasal pheromone transduction pathway in catarrhine primates. Proceedings of the National Academy of Sciences of the United States of America. 2003, 100 (14): 8337–8341.
Joseph A. Flaherty; John Marcell Davis; Philip G. Janicak. Psychiatry: Diagnosis & therapy. A Lange clinical manual. Appleton & Lange (Original from Northwestern University). 1993: 544. ISBN 0-8385-1267-4. The amount of time of sexual arousal needed to reach orgasm is variable — and usually much longer — in women than in men; thus, only 20–30% of women attain a coital climax. b. Many women (70–80%) require manual clitoral stimulation...
Mah K, Binik YM. The nature of human orgasm: a critical review of major trends. Clinical Psychology Review. 2001-01-07, 21 (6): 823–856. PMID 11497209. doi:10.1016/S0272-7358(00)00069-6. Women rated clitoral stimulation as at least somewhat more important than vaginal stimulation in achieving orgasm; only about 20% indicated that they did not require additional clitoral stimulation during intercourse.
Kammerer-Doak D, Rogers RG. Female Sexual Function and Dysfunction. Obstetrics and Gynecology Clinics of North America. 2008-06, 35 (2): 169–183. PMID 18486835. doi:10.1016/j.ogc.2008.03.006. Most women report the inability to achieve orgasm with vaginal intercourse and require direct clitoral stimulation ... About 20% have coital climaxes...
Robert Crooks; Karla Baur. Our Sexuality. Cengage Learning. 2010: 286–289 [2012-08-30]. ISBN 0495812943. Noncoital forms of sexual intimacy, which have been called outercourse, can be a viable form of birth control. Outercourse includes all avenues of sexual intimacy other than penile–vaginal intercourse, including kissing, touching, mutual masturbation, and oral and anal sex.
Malenka RC, Nestler EJ, Hyman SE. Chapter 15: Reinforcement and Addictive Disorders. Sydor A, Brown RY (编). Molecular Neuropharmacology: A Foundation for Clinical Neuroscience 2nd. New York: McGraw-Hill Medical. 2009: 364–365, 375. ISBN 9780071481274. The defining feature of addiction is compulsive, out-of-control drug use, despite negative consequences. ... compulsive eating, shopping, gambling, and sex–so-called "natural addictions"– ... Indeed, addiction to both drugs and behavioral rewards may arise from similar dysregulation of the mesolimbic dopamine system.
Dahabreh, Issa J. Association of Episodic Physical and Sexual Activity With Triggering of Acute Cardiac Events. Systematic Review and Meta-analysis.. JAMA: The Journal of the American Medical Association. 2011-03-23, 305 (12): 1225. doi:10.1001/jama.2011.336. Acute cardiac events were significantly associated with episodic physical and sexual activity; this association was attenuated among persons with high levels of habitual physical activity.
Pfortmueller CA, Koetter JN, Zimmermann H, Exadaktylos AK. Sexual activity-related emergency department admissions: Eleven years of experience at a Swiss university hospital. Emergency Medicine Journal. 2012, 30 (10): 846–850. PMID 23100321. doi:10.1136/emermed-2012-201845.
Corty EW, Guardiani JM. Canadian and American Sex Therapists' Perceptions of Normal and Abnormal Ejaculatory Latencies: How Long Should Intercourse Last?. The Journal of Sexual Medicine. 2008, 5 (5): 1251–1256. PMID 18331255. doi:10.1111/j.1743-6109.2008.00797.x.
Rod Plotnik; Haig Kouyoumdjian. Introduction to Psychology. Cengage Learning. 2010: 344. ISBN 0495903442. Inhibited female orgasm refers to a persistent delay or absence of orgasm after becoming aroused and excited. About 10% of women never reach orgasm...
Marlene B. Goldman; Rebecca Troisi; Kathryn M. Rexrode. Women and Health. Academic Press. 2012: 351 [2014-12-06]. ISBN 0123849799. (原始内容存档于2015-03-26).
Schouten BW, Bohnen AM, Groeneveld FP, Dohle GR, Thomas S, Bosch JL. Erectile dysfunction in the community: trends over time in incidence, prevalence, GP consultation and medication use—the Krimpen study: trends in ED. J Sex Med. 2010-07, 7 (7): 2547–53. PMID 20497307. doi:10.1111/j.1743-6109.2010.01849.x.
Tristano, Antonio G. Impact of rheumatoid arthritis on sexual function. World Journal of Orthopedics. 2014, 5 (2): 107. ISSN 2218-5836. doi:10.5312/wjo.v5.i2.107.
Greenwood, Nechama W.; Wilkinson, Joanne. Sexual and Reproductive Health Care for Women with Intellectual Disabilities: A Primary Care Perspective. International Journal of Family Medicine. 2013, 2013: 1–8. ISSN 2090-2042. doi:10.1155/2013/642472.
Madsen, S.; Collins, W. A. Differential predictions of young adult romantic relationships from transitory vs. longer romantic experiences during adolescence. Biennial Meeting of the Society for Research on Child Development. Atlanta, Georgia. 2005.
Seiffge-Krenke, I.; Lang, J. Forming and maintaining romantic relations from early adolescence to young adulthood: evidence of a developmental sequence. Biennial Meeting of the Society for Research on Adolescence. New Orleans, Louisiana. 2002.
Reed, E. J. Criminal Law and the Capacity of Mentally Retarded Persons to Consent to Sexual Activity. Virginia Law Review. 1997, 83 (4): 799–827. JSTOR 1073749. doi:10.2307/1073749.
Babb, Lawrence A. Redemptive Encounters: Three Modern Styles in the Hindu Tradition(Comparative Studies in Religion and Society). Oxford University Press. 1987. ISBN 0-7069-2563-7. Sexual intercourse is unnecessary for reproduction because the souls that enter the world during the first half of the Cycle are in possession of a special yogic power (yog bal) by which they conceive children.