Anal Intercourse: Clinical and Cultural Perspectives

Anal intercourse represents a multifaceted human sexual behavior characterized by the insertion of the erect penis into the anal canal of a partner, traversing significant biological, epidemiological, and sociocultural domains. While historically stigmatized, criminalized, or relegated to marginal discussions within medicine, contemporary scientific research views this practice through comprehensive frameworks encompassing sexual health, anatomical biomechanics, epidemiology, and interpersonal relational dynamics. Understanding this behavior requires an integrated biobehavioral paradigm that balances physiological considerations with evolving global normative patterns.

Anal Intercourse

1. Concise Definition

Anal intercourse, clinically termed coitus analis, refers to the penetrative sexual act involving the insertion and movement of the male penis into the rectum via the anus of a receptive partner, whether female or male. From an anatomical perspective, it entails the engagement of the external and internal anal sphincters, the anal transitional zone, and the distal rectal mucosa.

Beyond its physiological mechanics, the behavior encompasses distinct psychological, interpersonal, and epidemiological dimensions. Within contemporary sexological and biomedical discourse, anal intercourse is analyzed not as a pathology, but as an established variation of consensual human sexual expression that requires specific preventive health strategies, clinical awareness, and an understanding of subjective relational motives.

Public health literature categorizes the practice based on behavioral roles—specifically receptive anal intercourse (RAI) and insertive anal intercourse (IAI)—each carrying distinct biomechanical profiles, subjective experiential nuances, and epidemiological transmission probabilities for infectious pathogens.

2. Etymology & Linguistic Origin

The terminology associated with anal intercourse is derived from classical Latin roots that entered medical and juridical lexicons across centuries. The primary anatomical adjective anal originates from the classical Latin noun anus, which literally translates to “ring,” “circle,” or “annular passage.” The secondary component, intercourse, traces back to the Latin verb intercurrere (composed of inter-, meaning “between” or “among,” and currere, meaning “to run”), which evolved through Middle English and Anglo-French into entrecours, initially signifying commercial or communicative exchanges before acquiring its modern connotation of sexual coitus in the late 18th century.

Historically, medical, canonical, and legal authorities referred to the behavior using classical Latin terms such as coitus per anum (coitus through the anus) or subsumed it under broad ecclesiastical labels like sodomia (sodomy), a term rooted in the biblical narrative of Sodom. In early Western jurisprudence and canonical law, such designations often conflated distinct anatomical behaviors under moralistic or criminal categories. Modern biomedical science systematically replaced moralized terminology with descriptive, objective clinical designations—predominantly anal sex and anal intercourse—to facilitate non-judgmental epidemiological tracking, diagnostic assessment, and clinical communication.

3. Pronunciation & Grammatical Form

Pronunciation: The phonetic transcription in the International Phonetic Alphabet (IPA) is represented as /ˈeɪ.nəl ˈɪn.tər.kɔːrs/ in Received Pronunciation (British English) and /ˈeɪ.nəl ˈɪn.tɚˌkɔːrs/ in General American English.

Grammatical Form: Grammatically, anal intercourse operates as a compound noun phrase, functioning syntactically as an uncountable mass noun (e.g., “anal intercourse is documented across diverse demographic cohorts”). The term features several morphological and structural permutations across biomedical and sociolinguistic literature:

• Noun Phrase: Anal intercourse; alternatively receptive anal intercourse (RAI) or insertive anal intercourse (IAI).
• Adjectival Modifier: Anal-intercourse-related (e.g., “anal-intercourse-related mucosal microtrauma”).
• Synonymous Clinical Constructs: Coitus analis, anogenital penetration, and rectal coitus.
• Behavioral Designations: Clinicians and public health researchers commonly describe participants using the active participle or specialized acronyms such as “men who engage in insertive or receptive anal coitus.”

4. Detailed Conceptual Explanation

Anal intercourse occupies a unique anatomical, physiological, and sociological position in human sexuality. Unlike the vaginal canal, which possesses specialized stratified squamous epithelium capable of marked distension and endogenous transudative lubrication during autonomic sexual arousal, the rectum and anal canal evolved primarily for the storage and controlled elimination of waste. The anal canal measures approximately 2.5 to 4 centimeters in length, lined proximally by columnar epithelium and distally by sensitive non-keratinized anoderm. Consequently, engaging in anal intercourse involves overcoming the resting muscular tone of the anal sphincter complex, which comprises the involuntary internal anal sphincter (IAS) and the striated, voluntary external anal sphincter (EAS).

Because the distal rectal mucosa consists of a single layer of columnar epithelial cells joined by junctional complexes, it is particularly susceptible to micro-abrasions, frictional shearing stress, and inflammatory responses under mechanical force. Physiological accommodation requires systematic relaxation of the puborectalis muscle and the sphincter mechanism, often facilitated by foreplay, voluntary motor relaxation, and the application of exogenous water- or silicone-based lubricants. Without adequate preparation, mechanical trauma may induce mucosal tears, fissures, or transient hemorrhoidal inflammation, which underlines the importance of accurate somatic and sexological education.

From a psychological and neurological perspective, receptive anal intercourse can yield profound physical pleasure for individuals of all genders due to the high density of sensory nerve endings concentrated within the perineal branch of the pudendal nerve, the pelvic splanchnic nerves, and the perineal body. In biological males, anterior penetration through the rectal wall can mechanically stimulate the posterior aspect of the prostate gland, often precipitating intense orgasmic responses distinct from those generated solely via penile-shaft stimulation. In biological females, indirect mechanical stimulation of the posterior vaginal wall, the vestibular bulbs, and the crus of the clitoris can similarly induce heightened sexual arousal and coital orgasm.

Socially and interpersonally, anal intercourse carries distinct psychological meanings depending on the context in which it occurs. Research reveals that consensual participation is motivated by diverse factors, including erotic curiosity, experiential novelty, the intensification of intimacy, mutual trust, and role exploration. Conversely, the practice can be accompanied by distress, performance anxiety, or relational dissatisfaction if pursued under asymmetric relational power, insufficient communication, or coerced compliance. Modern sexological models emphasize that the psychological outcome of anal intercourse is profoundly moderated by communicative competence, emotional safety, mutual consent, and shared anatomical literacy.

5. Historical Development

The recorded history of anal intercourse spans multiple millennia, alternating between periods of ritualized institutionalization, severe legal repression, and contemporary clinical de-pathologization. Classical antiquity provides extensive documentation of receptive and insertive anal practices. In ancient Greece, structured pederastic relationships incorporated varying degrees of anogenital contact, frequently codified according to strict social hierarchies and age classes. Similarly, Roman erotic art, lyric poetry, and graffiti from Pompeii demonstrate widespread awareness and practice of anal intercourse across both heterosexual and same-sex pairings, bounded primarily by patriarchal status conventions regarding who could permissibly adopt the receptive versus insertive role.

With the rise and consolidation of Abrahamic theological dominance in Europe and the Mediterranean basin during Late Antiquity and the Middle Ages, anal intercourse became subject to intense religious proscription. Canonical scholars categorized the act as contra naturam (“against nature”) because it precluded the possibility of procreative conception. Secular legal statutes codified this theological stance into sodomy laws, which mandated severe punitive measures, including capital punishment, asset forfeiture, and lifelong imprisonment. These criminal codes were systematically exported globally throughout the 18th and 19th centuries via European colonial expansion, codifying prohibitions into penal statutes such as the British Empire’s Section 377, which affected legal frameworks across South Asia, Africa, and the Caribbean.

The late 19th and early 20th centuries witnessed the medicalization of human sexuality through the pioneering works of early sexologists such as Richard von Krafft-Ebing and Havelock Ellis. Krafft-Ebing’s Psychopathia Sexualis (1886) classified non-procreative acts, including coitus analis, as degenerate manifestations of psychosexual pathology. However, mid-20th-century empirical sex research pioneered by Alfred Kinsey fundamentally disrupted these paradigms. The Kinsey Reports (1948, 1953) revealed that anal intercourse was far more prevalent among both homosexual and heterosexual community samples than either legal or medical institutions had historically acknowledged.

The emergence of the HIV/AIDS epidemic in the early 1980s thrust anal intercourse into the forefront of global biomedical and public health research. Epidemiological investigations established that unprotected receptive anal intercourse carried the highest per-act transmission probability for HIV among all sexual behaviors. This realization catalyzed decades of intensive clinical inquiry, which ultimately yielded monumental biomedical breakthroughs, including harm-reduction frameworks, modern antiretroviral therapies, and pre-exposure prophylaxis (PrEP). Concurrently, legal reforms across democratic nations culminated in the decriminalization of private consensual sexual acts, exemplified by the landmark 2003 United States Supreme Court decision in Lawrence v. Texas, which formally dismantled remaining sodomy statutes.

6. Theoretical Foundations

Scholarly analysis of anal intercourse utilizes multiple theoretical paradigms spanning sexology, epidemiology, and sociology. These conceptual frameworks explain how physiological anatomy interacts with social scripts, interpersonal power, and disease transmission dynamics.

1. Sexual Script Theory: Developed by sociologists John Gagnon and William Simon, this theory posits that sexual behavior is guided by learned cultural scenarios, interpersonal negotiations, and intrapsychic fantasies. Applied to anal intercourse, the theory illustrates how traditional cultural scripts historical designated the practice as taboo or exclusively homosexual. Over the past three decades, mainstream media and popular culture have rewritten these scripts, integrating heterosexual anal intercourse into normative contemporary adult sexual repertoires, reshaping what partners anticipate, negotiate, and perform.

2. The Biopsychosocial Model: Formulated by George Engel, this framework evaluates anal intercourse at the intersection of biological factors (sphincteric integrity, mucosal immune defenses, neurotransmitter pathways), psychological variables (erotic self-efficacy, sexual pleasure motives, internalized stigma), and sociological structures (peer influences, healthcare access, heteronormative pressures). This comprehensive paradigm enables clinicians to address both somatic symptoms and relational or psychological distress without pathologizing the behavior itself.

3. Syndemics Theory: Formulated by medical anthropologist Merrill Singer, syndemics theory proves vital within epidemiological assessments of anal intercourse. It posits that concurrent, overlapping epidemics—such as systemic discrimination, poverty, mental health disorders, substance use, and sexually transmitted infections (STIs)—interact synergistically to heighten biomedical vulnerability during unprotected sexual practices. This approach transitions clinical perspectives away from individual moralizing and toward the structural determinants of sexual health.

7. Key Components, Types & Dimensions

Anal intercourse encompasses distinct physiological, behavioral, and clinical dimensions:

• Receptive Anal Intercourse (RAI): The physical act wherein an individual receives the partner’s penis into their anal canal and rectum. Biomechanically, this position involves dynamic accommodation of the sphincter mechanism and carries a higher epidemiological risk for acquiring mucosal pathogens due to direct exposure to seminal fluids and frictional epithelial microtrauma.
• Insertive Anal Intercourse (IAI): The act wherein an individual inserts their erect penis into the partner’s anal canal. This role involves exposure of the penile urethral meatus, glans, and prepuce to rectal fluids and enteric microflora, carrying distinct transmission dynamics for pathogens like gonorrhea and chlamydia.
• Behavioral Preparation and Lubrication Mechanics: A critical technical component involving voluntary pelvic floor relaxation and the generous application of exogenous lubricants. Because the rectal lumen does not self-lubricate, high-viscosity silicone or water-based formulas are required to mitigate frictional shear stresses and epithelial breakdown.
• Heterosexual Anal Intercourse: Anal penetration occurring between a biological male and female. Contemporary demographic surveys show significant lifetime prevalence rates among heterosexual adults, often linked to motives such as erotic exploration, pregnancy avoidance, or heightened intimacy.
• Same-Sex (MSM) Anal Intercourse: Anogenital contact between men who have sex with men. This behavior serves as a central modality of physical intimacy and pleasure for many gay and bisexual men, while remaining a primary focus of targeted clinical preventative interventions.
• Condom-Protected vs. Condomless Anal Intercourse: A critical behavioral categorization denoting whether barrier prophylaxis (latex or polyurethane condoms) is utilized to prevent exchanging fluids, enteric organisms, and viral pathogens.

8. Examples & Illustrative Cases

The following anonymized clinical and real-world case illustrations demonstrate the application of sexological and biomedical principles in clinical practice:

Case Illustration 1: Heterosexual Couple Navigating Dyspareunia and Communication Gaps
A 29-year-old cisgender female and her 31-year-old cisgender male partner presented to a sexual health clinic reporting severe physical pain and distress during attempted anal intercourse. Detailed assessment revealed that the couple had engaged in anal penetration abruptly following vaginal coitus without using supplemental exogenous lubrication or gradual sphincter relaxation techniques. The clinician identified superficial anal fissures on physical examination. The therapeutic intervention combined an educational briefing on anorectal anatomy, recommendations for high-viscosity silicone lubricants, pelvic floor relaxation exercises, and assertiveness training to empower the female partner to control the pace of penetration. At a two-month follow-up, the fissures had resolved, and the couple reported engaging in comfortable, communicative, and pain-free intimacy.

Case Illustration 2: Comprehensive Preventive Management in a Young MSM Individual
A 23-year-old gay cisgender male presented to an urban sexual health center requesting comprehensive screening. He reported engaging in frequent condomless receptive anal intercourse with non-monogamous partners. Rather than issuing moralizing risk warnings, the practitioner adopted a sex-positive harm reduction strategy. The provider initiated the patient on daily oral emtricitabine/tenofovir disoproxil fumarate for HIV pre-exposure prophylaxis (PrEP), administered the quadrivalent human papillomavirus (HPV) vaccine, and conducted three-site STI testing (pharyngeal, urogenital, and anorectal swabs). Anorectal nucleic acid amplification testing (NAAT) detected an asymptomatic rectal Chlamydia trachomatis infection, which was treated with oral doxycycline. Routine quarterly monitoring was scheduled to support ongoing sexual well-being.

9. Measurement & Assessment

Assessing anal intercourse within epidemiological, clinical, and psychometric contexts requires specialized tools that ensure reporting accuracy and mitigate social desirability bias.

1. Quantitative Epidemiological Instruments: Large-scale population health studies—such as the National Survey of Family Growth (NSFG) and the National Survey of Sexual Health and Behavior (NSSHB)—utilize Computer-Assisted Self-Interviewing (CASI) and Audio Computer-Assisted Self-Interviewing (ACASI). These methodologies offer privacy, demonstrably increasing disclosure rates for sensitive sexual behaviors compared to face-to-face clinician interviews.

2. Anorectal Clinical Examination and Laboratory Diagnostics: Somatic evaluations involve visual inspection of the perianal skin, digital rectal examination (DRE), and high-resolution anoscopy (HRA) to assess structural integrity, internal hemorrhoids, anal fissures, or mucosal dysplasia. Laboratory diagnostics rely on molecular assays, including Nucleic Acid Amplification Tests (NAAT) executed via self- or clinician-collected rectal swabs to detect Neisseria gonorrhoeae and Chlamydia trachomatis, alongside serological panels for syphilis, Hepatitis A, B, and C, and HIV-1/2.

3. Psychometric and Relational Inventories: Sexological research employs validated questionnaires to quantify attitudes, self-efficacy, and satisfaction related to sexual practices. Scales such as the Sexual Risks Scale, the Hurlbert Index of Sexual Assertiveness, and behavioral indices assessing communication surrounding anal sexual health capture the relational and psychological dynamics underpinning the behavior.

10. Applications & Practical Significance

The clinical and public health applications surrounding anal intercourse are essential to several medical disciplines:

Primary Care and Sexual Health Counseling: Clinicians must possess baseline cultural competence to discuss anal practices comfortably. A non-judgmental sexual history helps identify patients who require tailored preventive strategies, such as HPV vaccinations, routine extragenital STI screenings, and counseling on appropriate lubricant use to prevent mucosal injury.

Harm Reduction and Infectious Disease Prevention: The biomedical prevention landscape has evolved dramatically. The widespread implementation of PrEP has substantially lowered HIV transmission associated with both receptive and insertive anal intercourse. Furthermore, evidence establishing that Undetectable equals Untransmittable (U=U) reinforces the biological fact that an individual living with HIV on suppressive antiretroviral therapy cannot transmit the virus during intercourse, mitigating stigma and supporting emotional health.

Proctology and Gastroenterology: Clinicians specializing in colorectal surgery and gastroenterology frequently treat non-infectious complications resulting from mechanical friction during intercourse. Differential diagnosis of perianal pain, rectal bleeding, solitary rectal ulcers, and tone alterations necessitates detailed understanding of penetrative mechanics, helping clinicians distinguish between functional conditions, mechanical injuries, and infectious proctitis.

11. Research & Empirical Evidence

Contemporary sexological and public health research provides extensive empirical data regarding the prevalence, biomechanics, and epidemiological variables of anal intercourse across global populations.

Nationally representative surveys, such as the U.S. National Survey of Sexual Health and Behavior led by researchers Debby Herbenick, Michael Reece, and colleagues, indicate that anal intercourse is a prevalent behavior among both heterosexual adults and sexual minority populations. Data show that approximately 30% to 40% of adult women and 35% to 44% of adult men have engaged in heterosexual anal intercourse at least once during their lifetimes, challenging historical assumptions that the practice was exclusively confined to homosexual male demographics.

Epidemiological research led by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) provides robust per-act transmission probabilities for various infectious pathogens during unprotected intercourse. Seminal meta-analyses by Baggaley, White, and Boily calculate that the per-act risk of HIV transmission via unprotected receptive anal intercourse is approximately 1.4% (1 in 70), which is roughly ten to eighteen times higher than the per-act risk associated with receptive vaginal intercourse. The insertive partner faces an estimated per-act transmission risk of 0.11% (approximately 1 in 900), highlighting marked physiological differences in vulnerability driven by mucosal versus epithelial surfaces.

Additional empirical research explores the intersection of pornography consumption, relationship dynamics, and coercive pressures. Studies led by scholars such as Kimberly McBride and Cynthia Graham have documented that while many women report positive erotic experiences and physical pleasure during consensual anal intercourse, a notable minority report engaging in the practice primarily to satisfy partner expectations, occasionally reporting physical discomfort, involuntary pain, or lack of lubricant access. These findings underline the need for ongoing empirical research focused on sexual consent, pelvic health, and interpersonal assertiveness.

12. Cultural & Cross-Cultural Considerations

Socio-cultural attitudes toward anal intercourse vary markedly across global regions, shaped by historical traditions, religious orthodoxy, state legislation, and local gender norms.

In many Western, secularized societies, anal intercourse has undergone notable normalization. Pop-cultural media, feminist literature, and comprehensive sex education curricula have framed the practice as a consensual adult option centered on mutual pleasure, autonomy, and exploratory intimacy. Nevertheless, varying degrees of social embarrassment, prudishness, or moral hesitation persist across conservative subcultures within these nations.

In regions governed by conservative religious doctrines—including parts of the Middle East, North Africa, and sub-Saharan Africa—anal intercourse often carries severe social and legal condemnation. Several national penal codes enforce stringent penalties against consensual sodomy. Paradoxically, ethnographic research across diverse global settings has observed that some heterosexual individuals may engage in anal intercourse to preserve an anatomical marker of virginity (an intact vaginal hymen) prior to marriage, utilizing anal coitus to avoid both social stigma and pregnancy within strictly patriarchal moral frameworks.

In numerous Asian contexts, public dialogue regarding anal intercourse remains restrained due to widespread taboos surrounding sexuality in general. However, biomedical outreach initiatives across urban centers in Thailand, India, and China have successfully integrated culturally attuned education initiatives within sexual minority communities. These interventions emphasize peer-led harm reduction, digital sexual health engagement, and structural destigmatization.

13. Criticisms, Debates & Limitations

Academic discourse surrounding anal intercourse is marked by several ongoing debates across feminist theory, public health ethics, and clinical practice.

Feminist and Sociological Debates on Coercion: A central controversy centers on the influence of contemporary digital pornography on heterosexual expectations. Some feminist scholars argue that mainstream pornography frequently depicts anal intercourse without visible lubrication, realistic communication, or mutual consent, occasionally characterizing it as an act of male dominance or female degradation. Critics express concern that young women may experience coercion or feel pressured to participate to avoid partner abandonment, potentially experiencing physical pain or psychological distress. Conversely, sex-positive feminist scholars contend that anal intercourse can represent a powerful expression of bodily autonomy, agency, and unconventional erotic pleasure when chosen freely, resisting attempts to categorize all participants as passive victims of patriarchal expectations.

Public Health Messaging Balance: Another debate involves navigating the balance between epidemiological risk communication and sex-positive healthcare delivery. Early anti-AIDS campaigns frequently utilized fear-based messaging that inadvertently reinforced social stigma against men who have sex with men. Contemporary public health advocates argue that preventative messaging must celebrate consensual pleasure, provide accessible clinical prevention tools (such as condoms, lubricants, vaccines, and PrEP), and de-stigmatize anatomy without minimizing biological vulnerabilities.

Methodological Limitations in Empirical Research: Scientific study of anal intercourse continues to face methodological challenges. Self-reported survey data can be distorted by recall bias and social desirability effects. Furthermore, heterosexual studies frequently combine varied activities—such as single lifetime experiences and regular ongoing participation—into monolithic metrics, obscuring important differences in relational context, technique, lubrication frequency, and physical comfort.

14. Related Terms & Distinctions

To ensure precision in clinical and academic research, anal intercourse must be distinguished from several related concepts and anatomical behaviors:

• Anal Sex: A broad umbrella category that encompasses any erotic activity involving the perianal and anal region, including manual stimulation (fingering), oral-anal contact (anilingus or “rimming”), the insertion of sex toys (anal dildos, prostate massagers), and anal intercourse itself. Anal intercourse is specifically penetrative coitus involving the penis.
• Anilingus: The act of orally stimulating a partner’s perianal region and anal opening. Unlike anal intercourse, anilingus involves the tongue and mouth, carrying different sensory sensations and epidemiological profiles (such as transmission of enteric bacteria, Giardia, Hepatitis A, and oral HPV).
• Vaginal Intercourse (Coitus): The insertion of the penis into the muscular vaginal canal. Vaginal coitus differs markedly in biomechanics, as the vaginal tract is physiologically self-lubricating, lined with distensible stratified squamous epithelium, and linked to procreation.
• Anal Masturbation: The self-administered insertion of fingers, dilators, or erotic devices into one’s own anus for sexual pleasure, operating independently of an interpersonal partner dynamic.
• Sodomy: A historical, religious, and legal term historically applied to a wide range of non-procreative sexual acts (including anal coitus, oral sex, and bestiality). It has been largely retired from modern clinical and scientific vocabularies due to its pejorative and imprecise nature.

15. Summary / Key Takeaways

Anal intercourse represents an established, multifaceted consensual sexual practice characterized by the insertion of the penis into the receptive partner’s anal canal. Although historically criminalized, pathologized, and stigmatized across various cultures, it is recognized today within contemporary medicine, psychology, and public health as an expression of adult intimacy and pleasure across all sexual orientations.

Because the anorectal canal lacks natural glandular self-lubrication and is lined by a delicate mucosal epithelium, engaging in the practice requires informed anatomical awareness, voluntary relaxation of the pelvic floor and sphincter mechanism, and generous use of exogenous lubricants. These practices mitigate mechanical trauma, anal fissures, and functional distress. From a public health perspective, anal intercourse carries specific epidemiological considerations for sexually transmitted pathogens, necessitating accessible preventative interventions including condoms, comprehensive HPV vaccination, routine extragenital screening, and biomedical HIV prophylaxis (PrEP and U=U).

Ultimately, a holistic understanding of anal intercourse requires integrating physiological mechanics, clinical awareness, and respectful communication. By addressing both the relational dimensions of consent and the physical parameters of health, clinicians, researchers, and educators can support sexual health, personal autonomy, and informed physical well-being.

References

• Baggaley, R. F., White, R. G., & Boily, M. C. (2010). HIV transmission risk through anal intercourse: Systematic review, meta-analysis and rationale for HIV prevention interventions. International Journal of Epidemiology, 39(4), 1048–1063. https://doi.org/10.1093/ije/dyq057
• Centers for Disease Control and Prevention. (2021). Sexually Transmitted Infections Treatment Guidelines, 2021. U.S. Department of Health and Human Services. https://www.cdc.gov/std/treatment-guidelines/default.htm
• Gagnon, J. H., & Simon, W. (2005). Sexual Conduct: The Social Sources of Human Sexuality (2nd ed.). Aldine Transaction. https://www.routledge.com/Sexual-Conduct-The-Social-Sources-of-Human-Sexuality/Gagnon-Simon/p/book/9780202307596
• Herbenick, D., Reece, M., Schick, V., Sanders, S. A., Dodge, B., & Fortenberry, J. D. (2010). Sexual behavior in the United States: Results from a national probability sample of men and women ages 14–94. The Journal of Sexual Medicine, 7(Suppl 5), 255–265. https://doi.org/10.1111/j.1743-6109.2010.02012.x
• Kinsey, A. C., Pomeroy, W. B., & Martin, C. E. (1948). Sexual Behavior in the Human Male. W.B. Saunders. https://www.kinseyinstitute.org
• McBride, K. R., & Fortenberry, J. D. (2010). Heterosexual anal sexuality and anal sex behaviors: A review. The Journal of Sex Research, 47(2-3), 123–136. https://doi.org/10.1080/00224490903402538
• World Health Organization. (2016). Consolidated guidelines on HIV prevention, diagnosis, treatment and care for key populations. World Health Organization. https://www.who.int/publications/i/item/9789241511124