Gender identity is the personal sense of one's own gender. Gender identity can correlate with a person's assigned sex at birth or can differ from it. Gender expression typically reflects a person's gender identity, but this is not always the case. While a person may express behaviors, attitudes, and appearances consistent with a particular gender role, such expression may not necessarily reflect their gender identity. The term gender identity was originally coined by Robert J. Stoller in 1964.
All societies have a set of gender categories that can serve as the basis of a person's self-identity in relation to other members of society. In most societies, there is a basic division between gender attributes assigned to males and females, a gender binary to which most people adhere and which includes expectations of masculinity and femininity in all aspects of sex and gender: biological sex, gender identity, and gender expression. Some people do not identify with some, or all, of the aspects of gender assigned to their biological sex; some of those people are transgender, non-binary, or genderqueer. Some societies have third gender categories.
Gender identity is usually formed by age three. After age three, it is extremely difficult to change gender identity. Both biological and social factors have been suggested to influence its formation.
Age of formation
There are several theories about how and when gender identity forms, and studying the subject is difficult because children's lack of language requires researchers to make assumptions from indirect evidence. John Money suggested children might have awareness of and attach some significance to gender as early as 18 months to 2 years; Lawrence Kohlberg argued that gender identity does not form until age 3. It is widely agreed that core gender identity is firmly formed by age 3. At this point, children can make firm statements about their gender and tend to choose activities and toys which are considered appropriate for their gender (such as dolls and painting for girls, and tools and rough-housing for boys), although they do not yet fully understand the implications of gender. After age three, it is extremely difficult to change gender identity.
Martin and Ruble conceptualize this process of development as three stages: (1) as toddlers and preschoolers, children learn about defined characteristics, which are socialized aspects of gender; (2) around the ages of 5–7 years, identity is consolidated and becomes rigid; (3) after this "peak of rigidity", fluidity returns and socially defined gender roles relax somewhat. Barbara Newmann breaks it down into four parts: (1) understanding the concept of gender, (2) learning gender role standards and stereotypes, (3) identifying with parents, and (4) forming gender preference.
Factors influencing formation
Nature vs. nurture
Although the formation of gender identity is not completely understood, many factors have been suggested as influencing its development. In particular, the extent to which it is determined by socialization (environmental factors) versus innate (biological) factors is an ongoing debate in psychology, known as "nature versus nurture". Both factors are thought to play a role. Biological factors that influence gender identity include pre- and post-natal hormone levels. While genetic makeup also influences gender identity, it does not inflexibly determine it.
Social factors which may influence gender identity include ideas regarding gender roles conveyed by family, authority figures, mass media, and other influential people in a child's life. When children are raised by individuals who adhere to stringent gender roles, they are more likely to behave in the same way, matching their gender identity with the corresponding stereotypical gender patterns. Language also plays a role: children, while learning a language, learn to separate masculine and feminine characteristics and subconsciously adjust their own behavior to these predetermined roles. The social learning theory posits that children furthermore develop their gender identity through observing and imitating gender-linked behaviors, and then being rewarded or punished for behaving that way, thus being shaped by the people surrounding them through trying to imitate and follow them.
John Money was instrumental in the early research of gender identity, though he used the term gender role. He disagreed with the previous school of thought that gender was determined solely by biology. He argued that infants are born a blank slate and a parent could be able to decide their babies’ gender. In Money's opinion, if the parent confidently raised their child as the opposite sex, the child would believe that they were born that sex and act accordingly. Money believed that nurture could override nature.
A well-known example in the nature-versus-nurture debate is the case of David Reimer, otherwise known as "John/Joan". As a baby, Reimer went through a faulty circumcision, losing his male genitalia. Psychologist John Money convinced Reimer's parents to raise him as a girl. Reimer grew up as a girl, dressing in girl clothes and surrounded by girl toys, but did not feel like a girl. After he tried to commit suicide at age 13, he was told that he had been born with male genitalia, which he underwent surgery to reconstruct. This response went against Money's hypothesis that biology had nothing to do with gender identity or human sexual orientation.
Most did not dare to argue against Money's theory. Milton Diamond was a scientist who was one of the few to openly disagree with him and oppose his argument. Diamond had contributed to research involving pregnant rats that showed hormones played a major role in the behavior of different sexes. The researchers in the lab would inject the pregnant rat with testosterone, which would then find its way to the baby's bloodstream. The females that were born had genitalia that looked like male genitalia. The females in the litter also behaved like male rats and would even try to mount other female rats, proving that biology played a major role in animal behavior.
One criticism of the Reimer case is that Reimer lost his penis at the age of eight months and underwent sex reassignment surgery at seventeen months, which possibly meant that Reimer had already been influenced by his socialization as a boy. Bradley et al. (1998) report the contrasting case of a 26-year-old woman with XY chromosomes whose penis was lost and who underwent sex reassignment surgery between two and seven months of age (substantially earlier than Reimer), whose parents were also more committed to raising their child as a girl than Reimer's, and who remained a woman into adulthood. She reported that she had been somewhat tomboyish during childhood, enjoying stereotypically masculine childhood toys and interests, although her childhood friends were girls. While she was bisexual, having had relationships with both men and women, she found women more sexually attractive and they featured more in her fantasies. Her job at the time of the study was a blue-collar occupation that was practiced almost exclusively by men. Griet Vandermassen argues that since these are the only two cases being documented in scientific literature, this makes it difficult to draw any firm conclusions from them about the origins of gender identity, particularly given the two cases reached different conclusions. However, Vandermassen also argues that transgender people support the idea of gender identity as being biologically rooted, as they do not identify with their anatomical sex despite being raised and their behaviour reinforced according to their anatomical sex.
One study by Reiner et al. looked at fourteen genetic males who had suffered cloacal exstrophy and were thus raised as girls. Six of them changed their gender identity to male, five remained female and three had ambiguous gender identities (though two of them had declared they were male). All the subjects had moderate to marked interests and attitudes consistent with that of biological males. Another study, using data from a variety of cases from the 1970s to the early 2000s (including Reiner et al.), looked at males raised as females due to a variety of developmental disorders (penile agenesis, cloacal exstrophy or penile ablation). It found that 78% of those males raised as females were living as females. A minority of those raised as female later switched to male. However, none of the males raised as male switched their gender identity. Those still living as females still showed marked masculinisation of gender role behaviour and those old enough to reported sexual attraction to women. The study's authors caution drawing any strong conclusions from it due to numerous methodological caveats which were a severe problem in studies of this nature. Rebelo et al. argue that the evidence in totality suggests that gender identity is neither determined entirely by childhood rearing nor entirely by biological factors.
Several prenatal, biological factors, including genes and hormones, may affect gender identity. According to biologist Michael J. Ryan, gender identity is exclusive to humans.
Estimates of the number of people who are intersex range from 0.018% to 1.7%, depending on which conditions are counted as intersex. An intersex person is one possessing any of several variations in sex characteristics including chromosomes, gonads, sex hormones, or genitals that, according to the UN Office of the High Commissioner for Human Rights, "do not fit typical binary notions of male or female bodies". An intersex variation may complicate initial sex assignment and that assignment may not be consistent with the child's future gender identity. Reinforcing sex assignments through surgical and hormonal means may violate the individual's rights.
A 2005 study on the gender identity outcomes of female-raised 46,XY persons with penile agenesis, cloacal exstrophy of the bladder, or penile ablation, found that 78% of the study subjects were living as female, as opposed to 22% who decided to initiate a sex change to male in line with their genetic sex. The study concludes: "The findings clearly indicate an increased risk of later patient-initiated gender re-assignment to male after female assignment in infancy or early childhood, but are nevertheless incompatible with the notion of a full determination of core gender identity by prenatal androgens."
A 2012 clinical review paper found that between 8.5% and 20% of people with intersex variations experienced gender dysphoria. Sociological research in Australia, a country with a third 'X' sex classification, shows that 19% of people born with atypical sex characteristics selected an "X" or "other" option, while 52% are women, 23% men, and 6% unsure. At birth, 52% of persons in the study were assigned female, and 41% were assigned male.
A study by Reiner & Gearhart provides some insight into what can happen when genetically male children with cloacal exstrophy are sexually assigned female and raised as girls, according to an 'optimal gender policy' developed by John Money: in a sample of 14 children, follow-up between the ages of 5 to 12 showed that 8 of them identified as boys, and all of the subjects had at least moderately male-typical attitudes and interests, providing support for the argument that genetic variables affect gender identity and behavior independent of socialization.
Transgender and transsexuality
Some studies have investigated whether or not there is a link between biological variables and transgender or transsexual identity. Several studies have shown that sexually dimorphic brain structures in transsexuals are shifted away from what is associated with their birth sex and towards what is associated with their preferred sex. The volume of the central subdivision of the bed nucleus of a stria terminalis or BSTc (a constituent of the basal ganglia of the brain which is affected by prenatal androgens) of transsexual women has been suggested to be similar to women's and unlike men's, but the relationship between BSTc volume and gender identity is still unclear. Similar brain structure differences have been noted between gay and heterosexual men, and between lesbian and heterosexual women. Another study suggests that transsexuality may have a genetic component.
Research suggests that the same hormones that promote the differentiation of sex organs in utero also elicit puberty and influence the development of gender identity. Different amounts of these male or female sex hormones within a person can result in behavior and external genitalia that do not match up with the norm of their sex assigned at birth, and in a person acting and looking like their identified gender.
Social and environmental factors
Social scientists tend to assume that gender identities arise from social factors. In 1955, John Money proposed that gender identity was malleable and determined by whether a child was raised as male or female in early childhood. Money's hypothesis has since been discredited, but scholars have continued to study the effect of social factors on gender identity formation. In the 1960s and 1970s, factors such as the absence of a father, a mother's wish for a daughter, or parental reinforcement patterns were suggested as influences; more recent theories suggesting that parental psychopathology might partly influence gender identity formation have received only minimal empirical evidence, with a 2004 article noting that "solid evidence for the importance of postnatal social factors is lacking." A 2008 study found that the parents of gender-dysphoric children showed no signs of psychopathological issues aside from mild depression in the mothers.
Parental establishment of gender roles
Parents who do not support gender nonconformity are more likely to have children with firmer and stricter views on gender identity and gender roles. Recent literature suggests a trend towards less well-defined gender roles and identities, as studies of parental coding of toys as masculine, feminine, or neutral indicate that parents increasingly code kitchens and in some cases dolls as neutral rather than exclusively feminine. However, Emily Kane found that many parents still showed negative responses to items, activities, or attributes that were considered feminine, such as domestic skills, nurturance, and empathy. Research has indicated that many parents attempt to define gender for their sons in a manner that distances the sons from femininity, with Kane stating that "the parental boundary maintenance work evident for sons represents a crucial obstacle limiting boys options, separating boys from girls, devaluing activities marked as feminine for both boys and girls, and thus bolstering gender inequality and heteronormativity."
Many parents form gendered expectations for their child before it is even born, after determining the child's sex through technology such as ultrasound. The child thus is born to a gender-specific name, games, and even ambitions. Once the child's sex is determined, most children are raised in accordance with it to be a man or a woman, fitting a male or female gender role defined partly by the parents.
When considering the parents' social class, lower-class families typically hold traditional gender roles, where the father works and the mother, who may only work out of financial necessity, still takes care of the household. However, middle-class "professional" couples typically negotiate the division of labor and hold an egalitarian ideology. These different views on gender from a child's parents can shape the child's understanding of gender as well as the child's development of gender.
Within a study conducted by Hillary Halpern it was hypothesized, and proven, that parent behaviors, rather than parent beliefs, regarding gender are better predictors for a child's attitude on gender. It was concluded that a mother's behavior was especially influential on a child's assumptions of the child's own gender. For example, mothers who practiced more traditional behaviors around their children resulted in the son displaying fewer stereotypes of male roles while the daughter displayed more stereotypes of female roles. No correlation was found between a father's behavior and his children's knowledge of stereotypes of their own gender. It was concluded, however, that fathers who held the belief of equality between the sexes had children, especially sons, who displayed fewer preconceptions of their opposite gender.
Gender variance and non-conformance
Gender identity can lead to security issues among individuals that do not fit on a binary scale. In some cases, a person's gender identity is inconsistent with their biological sex characteristics (genitals and secondary sex characteristics), resulting in individuals dressing and/or behaving in a way which is perceived by others as outside cultural gender norms. These gender expressions may be described as gender variant, transgender, or genderqueer (or non-binary) (there is an emerging vocabulary for those who defy traditional gender identity), and people who have such expressions may experience gender dysphoria (traditionally called gender identity disorder or GID). Transgender individuals are often greatly affected by language and gender pronouns before, during, and after their transition.
In recent decades it has become possible to provide sex reassignment surgery. Some people who experience gender dysphoria seek such medical intervention to have their physiological sex match their gender identity; others retain the genitalia they were born with (see transsexual for some of the possible reasons) but adopt a gender role that is consistent with their gender identity.
History and definitions
The terms gender identity and core gender identity were first used with their current meaning—one's personal experience of one's own gender—sometime in the 1960s. To this day they are usually used in that sense, though a few scholars additionally use the term to refer to the sexual orientation and sexual identity categories gay, lesbian and bisexual.
Early medical literature
In late-19th-century medical literature, women who chose not to conform to their expected gender roles were called "inverts", and they were portrayed as having an interest in knowledge and learning, and a "dislike and sometimes incapacity for needlework". During the mid-1900s, doctors pushed for corrective therapy on such women and children, which meant that gender behaviors that were not part of the norm would be punished and changed. The aim of this therapy was to push children back to their "correct" gender roles and thereby limit the number of children who became transgender.
Freud and Jung's views
In 1905, Sigmund Freud presented his theory of psychosexual development in Three Essays on the Theory of Sexuality, giving evidence that in the pregenital phase children do not distinguish between sexes, but assume both parents have the same genitalia and reproductive powers. On this basis, he argued that bisexuality was the original sexual orientation and that heterosexuality was resultant of repression during the phallic stage, at which point gender identity became ascertainable. According to Freud, during this stage, children developed an Oedipus complex where they had sexual fantasies for the parent ascribed the opposite gender and hatred for the parent ascribed the same gender, and this hatred transformed into (unconscious) transference and (conscious) identification with the hated parent who both exemplified a model to appease sexual impulses and threatened to castrate the child's power to appease sexual impulses. In 1913, Carl Jung proposed the Electra complex as he both believed that bisexuality did not lie at the origin of psychic life, and that Freud did not give adequate description to the female child (Freud rejected this suggestion).
1950s and 1960s
During the 1950s and '60s, psychologists began studying gender development in young children, partially in an effort to understand the origins of homosexuality (which was viewed as a mental disorder at the time). In 1958, the Gender Identity Research Project was established at the UCLA Medical Center for the study of intersex and transsexual individuals. Psychoanalyst Robert Stoller generalized many of the findings of the project in his book Sex and Gender: On the Development of Masculinity and Femininity (1968). He is also credited with introducing the term gender identity to the International Psychoanalytic Congress in Stockholm, Sweden, in 1963. Behavioral psychologist John Money was also instrumental in the development of early theories of gender identity. His work at Johns Hopkins Medical School's Gender Identity Clinic (established in 1965) popularized an interactionist theory of gender identity, suggesting that, up to a certain age, gender identity is relatively fluid and subject to constant negotiation. His book Man and Woman, Boy and Girl (1972) became widely used as a college textbook, although many of Money's ideas have since been challenged.
In the late 1980s, Judith Butler began lecturing regularly on the topic of gender identity, and in 1990, she published Gender Trouble: Feminism and the Subversion of Identity, introducing the concept of gender performativity and arguing that both sex and gender are constructed.
Transgender people sometimes wish to undergo physical surgery to refashion their primary sexual characteristics, secondary characteristics, or both, because they feel they will be more comfortable with different genitalia. This may involve removal of penis, testicles or breasts, or the fashioning of a penis, vagina or breasts. In the past, sex assignment surgery has been performed on infants who are born with ambiguous genitalia. However, current medical opinion is strongly against this procedure, since many adults have regretted that these decisions were made for them at birth. Today, sex reassignment surgery is performed on people who choose to have this change so that their external sexual organs will match their gender identity.
In the United States, it was decided under the Affordable Care Act that health insurance exchanges would have the ability to collect demographic information on gender identity and sexual identity through optional questions, to help policymakers better recognize the needs of the LGBT community.
Gender dysphoria and gender identity disorder
Gender dysphoria (previously called "gender identity disorder" or GID in the DSM) is the formal diagnosis of people who experience significant dysphoria (discontent) with the sex they were assigned at birth and/or the gender roles associated with that sex: "In gender identity disorder, there is discordance between the natal sex of one's external genitalia and the brain coding of one's gender as masculine or feminine." The Diagnostic and Statistical Manual of Mental Disorders (302.85) has five criteria that must be met before a diagnosis of gender identity disorder can be made, and the disorder is further subdivided into specific diagnoses based on age, for example gender identity disorder in children (for children who experience gender dysphoria).
The concept of gender identity appeared in the Diagnostic and Statistical Manual of Mental Disorders in its third edition, DSM-III (1980), in the form of two psychiatric diagnoses of gender dysphoria: gender identity disorder of childhood (GIDC), and transsexualism (for adolescents and adults). The 1987 revision of the manual, the DSM-III-R, added a third diagnosis: gender identity disorder of adolescence and adulthood, nontranssexual type. This latter diagnosis was removed in the subsequent revision, DSM-IV (1994), which also collapsed GIDC and transsexualism into a new diagnosis of gender identity disorder. In 2013, the DSM-5 renamed the diagnosis gender dysphoria and revised its definition.
The authors of a 2005 academic paper questioned the classification of gender identity problems as a mental disorder, speculating that certain DSM revisions may have been made on a tit-for-tat basis when certain groups were pushing for the removal of homosexuality as a disorder. This remains controversial, although the vast majority of today's mental health professionals follow and agree with the current DSM classifications.
International human rights law
The Yogyakarta Principles, a document on the application of international human rights law, provide in the preamble a definition of gender identity as each person's deeply felt internal and individual experience of gender, which may or may not correspond with the sex assigned at birth, including the person's sense of the body (which may involve, if freely chosen, modification of bodily appearance or function by medical, surgical or other means) and other experience of gender, including dress, speech and mannerism. Principle 3 states that "Each person’s self-defined [...] gender identity is integral to their personality and is one of the most basic aspects of self-determination, dignity and freedom. No one shall be forced to undergo medical procedures, including sex reassignment surgery, sterilisation or hormonal therapy, as a requirement for legal recognition of their gender identity." and Principle 18 states that "Notwithstanding any classifications to the contrary, a person's sexual orientation and gender identity are not, in and of themselves, medical conditions and are not to be treated, cured or suppressed." Relating to this principle, the "Jurisprudential Annotations to the Yogyakarta Principles" observed that "Gender identity differing from that assigned at birth, or socially rejected gender expression, have been treated as a form of mental illness. The pathologization of difference has led to gender-transgressive children and adolescents being confined in psychiatric institutions, and subjected to aversion techniques – including electroshock therapy – as a 'cure'." The "Yogyakarta Principles in Action" says "it is important to note that while 'sexual orientation' has been declassified as a mental illness in many countries, 'gender identity' or 'gender identity disorder' often remains in consideration." These Principles influenced the UN declaration on sexual orientation and gender identity. In 2015, gender identity was part of a Supreme Court case in the United States called Obergefell v. Hodges in which marriage was no longer restricted between man and woman.
This section needs expansion. You can help by adding to it. (January 2020)
Kathleen Stock has written that because gender identity is based on a person's feelings, it is detached from both a person's sex and their gender (in the socially constructed sense). Stock also argues that because the concept of gender identity rarely comes up outside the context of gender dysphoria, "it would seem false to say that everyone has one".
No objective measurement or imaging of the human body exists for gender identity, as gender identity is part of one's subjective experience. Numerous instruments for assessing gender identity exist, including questionnaire-based, interview-based and task-based assessments. These have varying effect sizes among a number of specific sub-populations. Gender identity measures have been applied in clinical assessment studies of people with gender dysphoria or intersex conditions.
Non-binary gender identities
Some people, and some societies, do not construct gender as a binary in which everyone is either a boy or a girl, or a man or a woman. Those who exist outside the binary fall under the umbrella terms non-binary or genderqueer. Some cultures have specific gender roles that are distinct from "man" and "woman." These are often referred to as third genders.
In Samoan culture, or Faʻa Samoa, fa'afafine are considered to be a third gender. They are anatomically male but dress and behave in a manner considered typically feminine. According to Tamasailau Sua'ali'i (see references), fa'afafine in Samoa at least are often physiologically unable to reproduce. Fa'afafine are accepted as a natural gender, and neither looked down upon nor discriminated against. Fa'afafine also reinforce their femininity with the fact that they are only attracted to and receive sexual attention from straight masculine men. They have been and generally still are initially identified in terms of labour preferences, as they perform typically feminine household tasks. The Samoan Prime Minister is patron of the Samoa Fa'afafine Association. Translated literally, fa'afafine means "in the manner of a woman."
Hijras are officially recognized as third gender in the Indian subcontinent, being considered neither completely male nor female. Hijras have a recorded history in the Indian subcontinent since antiquity, as suggested by the Kama Sutra. Many hijras live in well-defined and organised all-hijra communities, led by a guru. These communities have consisted over generations of those who are in abject poverty or who have been rejected by or fled their family of origin. Many work as sex workers for survival.
The word "hijra" is a Hindustani word. It has traditionally been translated into English as "eunuch" or "hermaphrodite", where "the irregularity of the male genitalia is central to the definition". However, in general hijras are born male, only a few having been born with intersex variations. Some Hijras undergo an initiation rite into the hijra community called nirvaan, which involves the removal of the penis, scrotum, and testicles.
The khanith form an accepted third gender in Oman. The khanith are male homosexual prostitutes whose dressing is male, featuring pastel colors (rather than white, worn by men), but their mannerisms female. Khanith can mingle with women, and they often do at weddings or other formal events. Khaniths have their own households, performing all tasks (both male and female). However, similarly to men in their society, khaniths can marry women, proving their masculinity by consummating the marriage. Should a divorce or death take place, these men can revert to their status as khaniths at the next wedding.
Many indigenous North American Nations had more than two gender roles. Those who belong to the additional gender categories, beyond cisgender man and woman, are now often collectively termed "two-spirit" or "two-spirited". There are parts of the community that take "two-spirit" as a category over an identity itself, preferring to identify with culture or Nation-specific gender terms.
- Sexual orientation
- Identity (social science)
- Queer studies
- Queer theory
- Sex and gender distinction
- Social construction of gender
- Neuroscience of sex differences
- Sexual Orientation and Gender Expression in Social Work Practice, edited by Deana F. Morrow and Lori Messinger (2006, ISBN 0231501862), p. 8: "Gender identity refers to an individual's personal sense of identity as masculine or feminine, or some combination thereof."
- Campaign, Human Rights. "Sexual Orientation and Gender Identity Definitions".
- Summers, Randal W. (2016). Social Psychology: How Other People Influence Our Thoughts and Actions [2 volumes]. ABC-CLIO. p. 232. ISBN 9781610695923.
- American Psychological Association (December 2015). "Guidelines for Psychological Practice With Transgender and Gender Nonconforming People" (PDF). American Psychologist. 70 (9): 861. doi:10.1037/a0039906. PMID 26653312.
- STOLLER, ROBERT J. (November 1964). "The Hermaphroditic Identity of Hermaphrodites". The Journal of Nervous and Mental Disease. 139 (5): 453–457. doi:10.1097/00005053-196411000-00005. PMID 14227492. S2CID 22585295.
- V. M. Moghadam, Patriarchy and the politics of gender in modernising societies, in International Sociology, 1992: "All societies have gender systems."
- Carlson, Neil R.; Heth, C. Donald (2009), "Sensation", in Carlson, Neil R.; Heth, C. Donald (eds.), Psychology: the science of behaviour (4th ed.), Toronto, Canada: Pearson, pp. 140–41, ISBN 978-0205645244.
- Jack David Eller, Culture and Diversity in the United States (2015, ISBN 1317575784), p. 137: "most Western societies, including the United States, traditionally operate with a binary notion of sex/gender"
- For example, "transvestites [who do not identify with the dress assigned to their sex] existed in almost all societies." (G. O. MacKenzie, Transgender Nation (1994, ISBN 0879725966), p. 43.) "There are records of males and females crossing over throughout history and in virtually every culture. It is simply a naturally occurring part of all societies." (Charles Zastrow, Introduction to Social Work and Social Welfare: Empowering People (2013, ISBN 128554580X), p. 234, quoting the North Alabama Gender Center.)
- Bukatko, Danuta; Daehler, Marvin W. (2004). Child Development: A Thematic Approach. Houghton Mifflin. p. 495. ISBN 978-0-618-33338-7.
- Hine, F. R.; Carson, R. C.; Maddox, G. L.; Thompson, R. J. Jr; Williams, R. B. (2012). Introduction to Behavioral Science in Medicine. Springer Science & Business Media. p. 106. ISBN 978-1-4612-5452-2.
- Solomon, Kenneth (11 November 2013). Men in Transition: Theory and Therapy. Springer Science & Business Media. pp. 101–102. ISBN 978-1-4684-4211-3. Retrieved 10 January 2021.
- A few authorities say it forms between ages 3–4 rather than precisely at age 3, e.g. George J. Bryjak and Michael P. Soraka, Sociology: Cultural Diversity in a Changing World (ed. Karen Hanson), Allyn & Bacon, 1997; 209–45
- Newmann, Barbara (2012-12-20). Development Through Life: A Psychosocial Approach. Cengage Learning. p. 243. ISBN 978-1111344665.
- Christopher Bates Doob, Social Inequality and Social Stratification in US Society
- Martin, C.; Ruble, D. (2004). "Children's Search for Gender Cues Cognitive Perspectives on Gender Development". Current Directions in Psychological Science. 13 (2): 67–70. doi:10.1111/j.0963-7214.2004.00276.x. S2CID 33579865.
- International technical guidance on sexuality education: An evidence-informed approach (PDF). Paris: UNESCO. 2018. p. 18. ISBN 978-92-3-100259-5.
- Effects of male sex hormones on gender identity, sexual behavior, and cognitive function, Zhong Nan Da Xue Xue Bao, Yi Xue Ban (Journal of Central South University, Medical Sciences), April 2006, 31(2):149–61
- Money, John (1994). "The concept of gender identity disorder in childhood and adolescence after 39 years". Journal of Sex and Marital Therapy. 20 (3): 163–77. doi:10.1080/00926239408403428. PMID 7996589.
- Susan Golombok, Robyn Fivush, Gender Development (1994, ISBN 0521408628), p. 44: "When assigned and raised as boys, these genetic girls adopt a male gender identity and role, showing that a Y chromosome is not necessary for gender development to proceed in a male direction."
- Henslin, James M. (2001). Essentials of Sociology. Taylor & Francis. pp. 65–67, 240. ISBN 978-0-536-94185-5.
- "Factors Influencing Gender Identity".
- Williams, Michael, "Cultural Identity, Language Identity, Gender Identity", "The English Academy of South Africa", 2011
- Myers, David G. (2008). Psychology. New York: Worth.
- Martin, C. L.; Ruble, D. N.; Szkrybalo, J. (2002). "Cognitive theories of early gender development". Psychological Bulletin. 128 (6): 903–06. CiteSeerX 10.1.1.460.3216. doi:10.1037/0033-2909.128.6.903. PMID 12405137.
- Zucker, Kenneth J. (2006). Sytsma, Sharon E. (ed.). Ethics and Intersex. Springer Netherlands. p. 167. ISBN 978-1-4020-4313-0.
- "NOVA | Transcripts | Sex: Unknown | PBS". www.pbs.org. Retrieved 2018-12-07.
- Colapinto, John (2006). As nature made him : the boy who was raised as a girl (1st Harper Perennial ed.). New York: HarperCollins. ISBN 978-0061120565. OCLC 71012749.
- Nolen-Hoeksema (2014). Abnormal Psychology (6 ed.). McGraw-Hill. p. 368. ISBN 978-1308211503.
- Martin, Carol; Diane Ruble; Joel Szkrybalo (2002). "Cognitive Theories of Early Gender Development". Psychological Bulletin. 128 (6): 903–13. CiteSeerX 10.1.1.460.3216. doi:10.1037/0033-2909.128.6.903. PMID 12405137.
- Bradley, Susan J.; Oliver, Gillian D.; Chernick, Avinoam B.; Zucker, Kenneth J. (1 July 1998). "Experiment of Nurture: Ablatio Penis at 2 Months, Sex Reassignment at 7 Months, and a Psychosexual Follow-up in Young Adulthood". Pediatrics. 102 (1): e9. doi:10.1542/peds.102.1.e9. PMID 9651461.
The present case report is a long-term psychosexual follow-up on a second case of ablatio penis in a 46 XY male.
- Vandermassen, Griet. Who's afraid of Charles Darwin?: debating feminism and evolutionary theory. Rowman & Littlefield Publishers, 2005, pp.112-113
- Reiner, William G., and John P. Gearhart. "Discordant sexual identity in some genetic males with cloacal exstrophy assigned to female sex at birth." New England Journal of Medicine 350, no. 4 (2004): 333-341.
- Meyer-Bahlburg, Heino FL. "Gender identity outcome in female-raised 46, XY persons with penile agenesis, cloacal exstrophy of the bladder, or penile ablation." Archives of sexual behavior 34, no. 4 (2005): 423-438.
- Saraswat, A., Weinand, J. and Safer, J., 2015. Evidence supporting the biologic nature of gender identity. Endocrine Practice, 21(2), pp.199-204.
- Rebelo, Ethelwyn, Christopher P. Szabo, and Graeme Pitcher. "Gender assignment surgery on children with disorders of sex development: A case report and discussion from South Africa." Journal of Child Health Care 12, no. 1 (2008): 49-59.
- Ghosh, Shuvo. "Gender Identity". MedScape. Retrieved October 29, 2012.
- Ryan, Michael J. (2018-01-16). A Taste for the Beautiful: The Evolution of Attraction. Princeton University Press. p. 9. ISBN 978-1-4008-8915-0.
- Blackless, Melanie; Charuvastra, Anthony; Derryck, Amanda; Fausto-Sterling, Anne; Lauzanne, Karl; Lee, Ellen (March 2000). "How sexually dimorphic are we? Review and synthesis". American Journal of Human Biology. 12 (2): 151–66. doi:10.1002/(SICI)1520-6300(200003/04)12:2<151::AID-AJHB1>3.0.CO;2-F. ISSN 1520-6300. PMID 11534012. S2CID 453278.
- Sax, Leonard (August 2002). "How common is intersex? a response to Anne Fausto-Sterling". Journal of Sex Research. 39 (3): 174–178. doi:10.1080/00224490209552139. ISSN 0022-4499. PMID 12476264.
- "Free & Equal Campaign Fact Sheet: Intersex" (PDF). United Nations Office of the High Commissioner for Human Rights. 2015. Retrieved 28 March 2016.
- Mieszczak, J; Houk, CP; Lee, PA (Aug 2009). "Assignment of the sex of rearing in the neonate with a disorder of sex development". Curr Opin Pediatr. 21 (4): 541–47. doi:10.1097/mop.0b013e32832c6d2c. PMC 4104182. PMID 19444113.
- Council of Europe; Commissioner for Human Rights (April 2015), Human rights and intersex people, Issue Paper
- Swiss National Advisory Commission on Biomedical Ethics NEK-CNE (November 2012). On the management of differences of sex development. Ethical issues relating to "intersexuality".Opinion No. 20/2012 (PDF). 2012. Berne. Archived from the original (PDF) on 2015-04-23. Retrieved 2016-10-06.
- World Health Organization (2015). Sexual health, human rights and the law. Geneva: World Health Organization. ISBN 978-9241564984.
- Meyer-Bahlburg, HF (2005). "Gender identity outcome in female-raised 46,XY persons with penile agenesis, cloacal exstrophy of the bladder, or penile ablation". Archives of Sexual Behavior. 34 (4): 423–38. doi:10.1007/s10508-005-4342-9. PMID 16010465. S2CID 34971769.
- Furtado P. S.; et al. (2012). "Gender dysphoria associated with disorders of sex development". Nat. Rev. Urol. 9 (11): 620–27. doi:10.1038/nrurol.2012.182. PMID 23045263. S2CID 22294512.
- "New publication "Intersex: Stories and Statistics from Australia"". Organisation Intersex International Australia. February 3, 2016. Archived from the original on 2016-08-29. Retrieved 2016-08-18.
- Jones, Tiffany; Hart, Bonnie; Carpenter, Morgan; Ansara, Gavi; Leonard, William; Lucke, Jayne (2016). Intersex: Stories and Statistics from Australia (PDF). Cambridge, UK: Open Book Publishers. ISBN 978-1-78374-208-0. Archived from the original (PDF) on 14 September 2016. Retrieved 2 February 2016.
- Rosario, Vernon. "Reiner & Gearhart's NEJM Study on Cloacal Exstrophy – Review by Vernon Rosario, M.D., Ph.D". Intersex Society of North America.
- E. Vilain, Genetics of intersexuality, J. Gay Lesbian Psychother. 10 (2006) 9–26.
- A. Fleming, E. Vilain, The endless quest for sex determination genes, Clin.Genet. 67 (2005) 15–25.
- Savic, I.; Arver, S. (2011). "Sex dimorphism of the brain in male-to-female transsexuals". Cerebral Cortex. 21 (11): 2525–533. doi:10.1093/cercor/bhr032. PMID 21467211. Concluded that gynephilic trans women had brains like men's, but in a few areas, trans women's brains were different from both men's and women's brains.
- Gizewski, E. R.; Krause, E.; Schlamann, M.; Happich, F.; Ladd, M. E.; Forsting, M.; Senf, W. (2009). "Specific cerebral activation due to visual erotic stimuli in male-to-female transsexuals compared with male and female controls: An fMRI study". Journal of Sexual Medicine. 6 (2): 440–48. doi:10.1111/j.1743-6109.2008.00981.x. PMID 18761592. Found that a sample of androphilic trans women was shifted towards the female direction in brain responses.
- Rametti, G.; Carrillo, B.; Gómez-Gil, E.; Junque, C.; Zubiarre-Elorza, L.; Segovia, S.; Gomez, Á; Guillamon, A. (2011). "White matter microstructure in female to male transsexuals before cross-sex hormonal treatment. A diffusion tensor imaging study". Journal of Psychiatric Research. 45 (2): 199–204. doi:10.1016/j.jpsychires.2010.05.006. PMID 20562024. Found that the white matter pattern in gynephilic trans men was shifted in the direction of biological males even before the female-to-male transsexuals started taking male hormones.
- Psychology The Science Of Behaviour, pg 418, Pearson Education, Neil R.Carlson
- Zhou, J.N.; Hofman, M.A.; Gooren, L.J.; Swaab, D.F. (1995). "A sex difference in the human brain and its relation to transsexuality". Nature (Submitted manuscript). 378 (6552): 68–70. Bibcode:1995Natur.378...68Z. doi:10.1038/378068a0. hdl:20.500.11755/9da6a0a1-f622-44f3-ac4f-fec297a7c6c2. PMID 7477289. S2CID 4344570.
- Rosenthal, Stephen M. (December 2014). "Approach to the Patient: Transgender Youth: Endocrine Considerations". The Journal of Clinical Endocrinology & Metabolism. 99 (12): 4379–4389. doi:10.1210/jc.2014-1919. PMID 25140398.
the sexually dimorphic differentiation of the BSTc in humans is not present until puberty, in contrast to rats, where such differences in the BST occur in the early postnatal period and apparently require perinatal differences in T levels (44, 45). Given that many transgender adolescents experience significant gender dysphoria before puberty (and before sex differences in BSTc volume emerge), the relationship between BSTc volume and gender identity would appear to be unclear.
- LeVay S (August 1991). "A difference in hypothalamic structure between heterosexual and homosexual men". Science. 253 (5023): 1034–37. Bibcode:1991Sci...253.1034L. doi:10.1126/science.1887219. PMID 1887219. S2CID 1674111.
- Byne W, Tobet S, Mattiace LA, et al. (September 2001). "The interstitial nuclei of the human anterior hypothalamus: an investigation of variation with sex, sexual orientation, and HIV status". Horm Behav. 40 (2): 86–92. doi:10.1006/hbeh.2001.1680. PMID 11534967. S2CID 3175414.
- Male transsexual gene link found BBC News 26 October 2008 (accessed 26 October 2008)
- Oswalt, Angela. "Factors Influencing Gender Identity". Seven Countries Services, Inc. Archived from the original on April 15, 2013. Retrieved October 29, 2012.
- Kiecolt, K. Jill; Hughes, Michael; Momsplair, Hans (2019). "Gender Identity Among U.S. Adults". In Stets, Jan E.; Serpe, Richard T. (eds.). Identities in Everyday Life. Oxford University Press. p. 195. ISBN 978-0-1908-7306-6.
- J. Money, J. G. Hampson, and J. L. Hampson, An examination of some basic sexual concepts, 1955
- A. L. C. de Vries, et al., Gender Dysphoria and Disorders of Sex Development (2013, ISBN 1461474418)
- Anne Fausto-Sterling, Sexing the Body: Gender Politics and the Construct
- D. F. Swaab, Sexual differentiation of the human brain: relevance for gender identity, transsexualism and sexual orientation, in Gynecological Endocrinology, 2004: "...direct effects of testosterone on the developing fetal brain are of major importance for the development of male gender identity and male heterosexual orientation. Solid evidence for the importance of postnatal social factors is lacking."
- M. S. C. Wallien, Psychosexual outcome of gender-dysphoric children (2008)
- M Weinraub, LP Clemens, A Sockloff, T Ethridge, The development of sex role stereotypes in the third year: relationships to gender labeling, gender identity, sex-types toy preference, and family characteristics, in Child Development, 1984: "Previous investigators have failed to observe a relationship between parental attitudes and children's early sex role acquisition..."
- Spade, Joan (2010). The Kaleidoscope of Gender. London: Sage. pp. 177–84. ISBN 978-1-4129-7906-1.
- Halpern, Hillary Paul (2015). "Parents' Gender Ideology and Gendered Behavior as Predictors of Children's Gender-Role Attitudes: A Longitudinal Exploration". Sex Roles. 74 (11–12): 527–42. doi:10.1007/s11199-015-0539-0. PMC 4945126. PMID 27445431.
- Hoogensen, Gunhild; Rottem, Svein Vigeland (2016-06-29). "Gender Identity and the Subject of Security". Security Dialogue. 35 (2): 155–71. doi:10.1177/0967010604044974. S2CID 55600340.
- Blackless, Melanie; Besser, M.; Carr, S.; Cohen-Kettenis, P.T.; Connolly, P.; De Sutter, P.; Diamond, M.; Di Ceglie, D.; Higashi, Y.; Jones, L.; Kruijver. F.P.M.; Martin, J.; Playdon, Z-J.; Ralph, D.; Reed, T.; Reid, R.; Reiner, W.G.; Swaab, D.; Terry, T.; Wilson, P.; Wylie, K. (2003). "Atypical Gender Development – A Review". International Journal of Transgenderism. 9: 29–44. doi:10.1300/J485v09n01_04. S2CID 216148638. Archived from the original on 2008-10-07. Retrieved 2008-09-28.
- "Toronto couple defend move to keep baby's sex secret". BBC News. 27 May 2011.
- "Words Matter: Affirming Gender Identity Through Language". 18 May 2016.
- Boles, 2013. p. 101: "Gender identity is the individual's personal and private experience of his/her gender."
- "The term 'gender identity' was used in a press release, November 21, 1966, to announce the new clinic for transsexuals at The Johns Hopkins Hospital. It was disseminated in the media worldwide, and soon entered the vernacular. ... gender identity is your own sense or conviction of maleness or femaleness." Money, John (1994). "The concept of gender identity disorder in childhood and adolescence after 39 years". Journal of Sex and Marital Therapy. 20 (3): 163–77. doi:10.1080/00926239408403428. PMID 7996589.
- Handbook of the Psychology of Women and Gender (2004, ISBN 0471653578), p. 102: "Gender identity was introduced into the professional lexicon by Hooker and Stoller almost simultaneously in the early 1960s (see Money, 1985). For example, Stoller (1964) used the slightly different term core gender identity..."
- Brym, Roberts, Lie, Rytina. "Sociology". Nelson Education Ltd., 2013.
- Padawer, Ruth. "What's So Bad About a Boy Who Wants to Wear a Dress?". The New York Times. Retrieved October 29, 2012.
- Freud, Sigmund (1931). "Female Sexuality". The Standard Edition of the Complete Psychological Works of Sigmund Freud. 21: 229.
- Haraway, Donna (1991). Simians, Cyborgs, and Women: The Reinvention of Nature. London: Free Association Books. p. 133. ISBN 978-0-415-90386-8.
- Fixing Sex: Intersex, Medical Authority, and Lived Experience by Katrina Karkazis, Duke University Press, November 2008
- Butler, Judith (1990). Gender Trouble: Feminism and the Subversion of Identity. London: Routledge. pp. front/backmatter. ISBN 978-0415389556.
- Diamond, Milton (2002). "Sex and Gender are Different: Sexual Identity and Gender Identity are Different". Clinical Child Psychology & Psychiatry. 7 (3): 320–34. doi:10.1177/1359104502007003002. S2CID 144721800.
- Baker, Kellan. "FAQ: Collecting Sexual Orientation and Gender Identity Data". Center for American Progress. Retrieved October 29, 2012.
- "Gender Identity Disorder | Psychology Today." Psychology Today: Health, Help, Happiness Find a Therapist. Psychology Today, 24 Oct. 2005. Web. 17 Dec. 2010. http://www.psychologytoday.com/conditions/gender-identity-disorder.
- "Gender Dysphoria Organization Research and Education - About Gender Dysphoria". web.archive.org. 2010-03-06. Retrieved 2021-05-13.
- Zucker, KJ; Spitzer, RL (Jan–Feb 2005). "Was the gender identity disorder of childhood diagnosis introduced into DSM-III as a backdoor maneuver to replace homosexuality? A historical note". Journal of Sex and Marital Therapy. 31 (1): 31–42. doi:10.1080/00926230590475251. PMID 15841704. S2CID 22589255.
- Parry, Wynne (June 4, 2013). "DSM-5 Reflects Shift In Perspective On Gender Identity". The Huffington Post. Retrieved 2015-10-23.
- The Yogyakarta Principles, Principle 3. The Right to recognition before the law
- The Yogyakarta Principles, Principle 18. Protection from medical abuse
- Jurisprudential Annotations to the Yogyakarta Principles, p. 43 Archived November 22, 2010, at the Wayback Machine
- "Activist's Guide to the Yogyakarta Principles, p. 100" (PDF). Archived from the original (PDF) on 2017-01-04. Retrieved 2018-02-14.
- Stock, Kathleen (1 July 2019). "Can you Change Your Gender?". The Philosopher. ISSN 0967-6074. Retrieved 4 January 2020.
- Dahlen, Sara (2 January 2020). "De-sexing the Medical Record? An Examination of Sex Versus Gender Identity in the General Medical Council's Trans Healthcare Ethical Advice". The New Bioethics. 26 (1): 38–52. doi:10.1080/20502877.2020.1720429. PMID 32011214.
No genetic marker, biochemical test, brain imaging, or objective measurement exists in medical practice for gender identity, which is itself of an unknown aetiology (NHS 2016, Bizic et al. 2018, Gerritse et al. 2018, Bewley et al. 2019). The central claim rests on a consistent declarative statement of the trans patient’s subjective experience of self-hood. Therefore, we cannot prove or disprove a gender identity. Gender identity is a deeply held, spiritually significant, personal belief that can neither be confirmed nor rebutted by external evidence and biological data.
- Zucker, Kenneth J. (August 2005). "Measurement of Psychosexual Differentiation". Archives of Sexual Behavior. 34 (4): 375–388. doi:10.1007/s10508-005-4336-7. PMID 16010461. S2CID 18953324.
- Sua'ali'i, Tamasailau, "Samoans and Gender: Some Reflections on Male, Female and Fa'afafine Gender Identities", in: Tangata O Te Moana Nui: The Evolving Identities of Pacific Peoples in Aotearoa/New Zealand, Palmerston North (NZ): Dunmore Press, 2001, ISBN 0-86469-369-9
- Schmidt, Johanna (May 2003). "Paradise Lost? Social Change and Fa'afafine in Samoa". Current Sociology. 51 (3): 417–32. doi:10.1177/0011392103051003014. S2CID 145438114.
- Field, Michael (5 July 2011). "Transsexuals hailed by Samoan PM". Stuff.co.nz. Retrieved 1 October 2011.
- Paul L. Vasey, Nancy H. Bartlett, "What Can the Samoan "Fa'afafine" Teach Us About the Western Concept of Gender Identity Disorder in Childhood?", Biology and Medicine, 50.4 (2007) 481–90
- Shaw et al. 2017 harvnb error: no target: CITEREFShawBarbourDuncanFreehling-Burton2017 (help), Bevan 2016, p. 70 harvnb error: no target: CITEREFBevan2016 (help)
- "7 Countries Giving Transgender People Fundamental Rights the U.S. Still Won't". mic.com. Retrieved 17 June 2016.
"Hijras and Bangladesh: The creation of a third gender". pandeia.eu. 2 December 2013. Archived from the original on 5 July 2016. Retrieved 17 June 2016.
- Nanda 1985, pp. 35–54 "The most significant relationship in the hijra community is that of the guru (master, teacher) and chela (disciple)." harvnb error: no target: CITEREFNanda1985 (help)
Cohen 1995, "Hijras are organized into households with a hijra guru as head, into territories delimiting where each household can dance and demand money from merchants" harvnb error: no target: CITEREFCohen1995 (help)
- Nanda 1999, p. 116 "None of the hijra narratives I recorded supports the widespread belief in India that hijras recruit their membership by making successful claims on intersex infants. Instead, it appears that most hijras join the community in their youth, either out of a desire to more fully express their feminine gender identity, under the pressure of poverty, because of ill-treatment by parents and peers for feminine behavior, after a period of homosexual prostitution or for a combination of these reasons.". sfn error: no target: CITEREFNanda1999 (help)
- Nanda 1996 harvnb error: no target: CITEREFNanda1996 (help)
- Reddy 2010, p. 243 "By and large, the Hindi/Urdu term hijra is used more often in the north of the country, whereas the Telugu term kojja is more specific to the state of Andhra Pradesh, of which Hyderabad is the capital." harvnb error: no target: CITEREFReddy2010 (help)
Chettiar 2015, "The Urdu and Hindi word "hijra" may alternately be romanized as hijira, hijda, hijada, hijara, hijrah and is pronounced "heejra" or "heejda"; harvnb error: no target: CITEREFChettiar2015 (help)
- Nanda 1999. sfn error: no target: CITEREFNanda1999 (help)
- Nanda 1991, "Among thirty of my informants, only one appeared to have been born intersexed.". sfn error: no target: CITEREFNanda1991 (help)
- Lorber, Judith. Paradoxes of Gender. Yale University Press:Yale, 1994. pp. 94–95.
- Hunt, Sarah (2016). "An Introduction to the Health of Two-Spirit People: Historical, contemporary and emergent issues" (PDF). National Collaborative Centre Aboriginal Health. Archived from the original (PDF) on 2017-02-02.
- Marciano, Avi (2014). "Living the VirtuReal: Negotiating Transgender Identity in Cyberspace". Journal of Computer-Mediated Communication. 19 (4): 824–838. doi:10.1111/jcc4.12081.