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A Universally Accepted Definition of Gender Will Positively Impact Societal Understanding, Acceptance, and Appropriateness of Health Care

Open AccessPublished:May 21, 2020DOI:https://doi.org/10.1016/j.mayocp.2020.01.031

      Abstract

      When individuals do not conform to stereotypes associated with “male” or “female,” they are often ridiculed, bullied, and rejected, which leads to depression, psychological problems, and even suicide. The number of individuals who identify themselves as transgender, gender queer, or who do not conform to societal norms with respect to gender appears to be increasing. Despite this apparent increase, clinicians and health care facilities are ill-prepared to meet the needs of these individuals in a professional and appropriate manner. Unfortunately, there is an inherit distrust of the medical community by individuals who do not conform to societal norms with respect to gender because of a perception that the medical community does not understand the unique challenges of these individuals. Therefore, reducing the social stigma associated with gender nonconforming individuals is one way to begin to break down barriers of distrust and enhance communication within and outside the medical community. In this review, we discuss the scant amount of scientific data on the biological origins of gender identity. We highlight the fact that the biological definition of gender remains elusive in part because molecular and biological techniques have not been available to accurately probe the development of gender identity. We therefore advocate for the importance of enhancing our knowledge of the origins of gender identity with advanced scientific tools. Enhancing scientific understanding of the biological origins of gender identity may reduce stigma and barriers to care.
      Article Highlights
      • There is an increasing number of individuals who self-identify as gender nonconforming, including those who identify as transgender individuals. Transgender individuals are defined as individuals whose sense of self/gender identity differs from their natal sex. Transgender men are individuals born with two X chromosomes but whose gender identity is male. Transgender females are individuals born with an X and a Y chromosome but whose gender identity is female. This is a population not to be confused with those with defined disorders of sex development.
      • There is a significant confusion in the health care community as to how to approach and care for gender nonconforming and transgender individuals resulting in suboptimal clinical care, bias, prejudice, and stereotyping. Data suggest that lack of accessibility and inappropriate health care can lead to increased suicides in gender nonconforming and transgender individuals.
      • Some transgender individuals “know/sense” there is a mismatch between their gender identity and their natal sex before socialization and experiencing gender stereotypes.
      • Brain imaging studies show brain patterning and size of sexually dimorphic brain nuclei of transgender individuals is more similar to the individual’s gender identity than their natal sex.
      • Windows of opportunity may exist where there is a disconnect between physiologic development of the brain and genitals such that natal sex differs from gender identity.

      Case Study

      Consider “Jack,” a 28-year-old white man who presents to his drill sergeant in the US Army with the concern that his gender identity does not match his natal sex. Jack tells his drill sergeant he is seeking the opportunity to access medical care to begin cross-hormone therapy to facilitate alignment with his gender identity. The fifth of seven brothers, Jack was raised in a predominately male household; yet, from the moment he could speak, he knew his gender identity did not match his birth assigned sex. Jack struggled during the onset of male puberty with bouts of depression and anxiety. Adolescence was difficult for Jack — he felt the weight of tremendous peer pressure to participate in typical male-dominated sports and activities and to hide his feelings about his gender. His parents, who did not understand his struggles with gender identity, encouraged Jack to surround himself with more men in hopes that male socialization would “inspire” Jack to be less feminine. Jack’s parents eventually insisted that Jack join the US Army. Jack had been an exemplary soldier for the past 5 years with numerous meritorious service medals; nonetheless, Jack is certain about their feminine gender identity and is looking for ways, with the assistance of the military medical program, to begin to seek gender-affirming care.

      Introduction

      Society views sex as binary and interacts with individuals based on stereotypes typically assigned to physical characteristics associated with “male” or “female.” When it comes to the concepts of sex and gender, most of society views any deviation from stereotypes of male or female as societally taboo. When it comes to health care institutions, most clinicians and health care providers are unfamiliar with the importance of respecting a person’s gender identity. Unfortunately, this is exacerbated by the fact there are no standardized scientific definitions of gender and there are no clear-cut ways to factor gender into health care.
      The introductory case scenario discussing Jack is designed to remind us of the importance of understanding gender’s complexity. Gender identity is a term used to refer to a person's sense of being male, female, neither, or a combination of both. Terms used to describe persons whose gender identity does not align with the sex recorded at birth include: gender nonconforming, transgender, transsexual, trans, gender nonbinary, gender incongruent, and genderqueer. These terms differ from cisgender, which is used to describe persons whose sex recorded at birth aligns with their sense of gender identity. Gender dysphoria is a term used to describe a mental health diagnosis referring to the discomfort of misalignment of gender identity and the sex recorded at birth. In the case study above, Jack would be characterized as displaying symptoms of gender dysphoria. Jack is seeking the ability to access medical care to transition, or receive cross-sex hormone therapy to achieve gender affirmation or gender confirmation which refers to alignment of physical characteristics with gender identity. Not all gender nonbinary or transgender persons have gender dysphoria or elect for cross-sex hormone therapy.
      Gender nonconforming, gender nonbinary, transgender, and genderqueer individuals differ from individuals who are identified with disorders of sex development (DSDs). DSDs are defined as conditions involving the following elements: congenital development of ambiguous genitalia (eg, 46,XX virilizing congenital adrenal hyperplasia; clitoromegaly; and micropenis); congenital disjunction of internal and external sex anatomy (eg, complete androgen insensitivity syndrome and 5-alpha reductase deficiency); incomplete development of sex anatomy (eg, vaginal agenesis and gonadal agenesis); sex chromosome anomalies (eg, Turner syndrome; Klinefelter syndrome; and sex chromosome mosaicism); and disorders of gonadal development (eg, ovotestes).
      • Lee P.A.
      • Houk C.P.
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      • et al.
      Consensus statement on management of intersex disorders. International Consensus Conference on Intersex.
      DSDs include anomalies of the sex chromosomes, the gonads, the reproductive ducts, and the genitalia.
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      • Ahmed S.F.
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      Consensus statement on management of intersex disorders. International Consensus Conference on Intersex.

      Where Does Sense of Gender Identity Reside?

      Development of sex in humans comprises irreversible sexual differentiation of the external genitalia during embryogenesis. There are some individuals born with anatomical ambiguities in their genitalia such that they are not clearly classified as male or female. For these individuals over most of the 20th century, doctors surgically altered ambiguous genitals to become whichever required the least amount of reconstructive surgery. In fact, it had been believed individuals would adapt to surgically altered genitalia and conform to the sex indicated by the gonads. In a study of genetically male children given female genitalia, 8 of 14 subjects identified as male despite the presence of surgically constructed female genitalia.
      • Reiner W.
      • Gearhart J.
      Discordant sexual identity in some genetic males with cloacal exstrophy assigned to female sex at birth.
      This study illustrates the importance of understanding the origins of gender identity which appear to occur outside the presence of genitalia. New technologies and methodologies should be incorporated into medical decisions about which genitalia are most appropriate for individuals born with ambiguous genitalia.
      During the developmental window from 2 to 3 years of age, it is believed the perception of gender identity ensues. As early as 2 years of age, children develop facility with gender labeling, including pronouns.
      • Zosuls K.M.
      • Ruble D.N.
      • Tamis-Lemonda C.S.
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      The acquisition of gender labels in infancy: implications for gender-typed play.
      There are data suggesting that between 0.6% and 2.7% of children within in this age range report some degree of gender incongruence, although this may depend on the age the children were studied and the gender-related definitions used.
      • Rider G.N.
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      Health and care utilization of transgender and gender nonconforming youth: a population-based study.
      Additional epidemiologic studies are needed to facilitate defining gender identity among children.
      Sexual maturation of secondary sex characteristics occurs during puberty (eg, sex-specific body proportions, bone size, and pubertal voice change), which is followed by sex-specific development of extragenital tissues and organs. During the onset of puberty children are increasingly able to articulate their gender identity. This developmental window becomes particularly stressful for children who report gender incongruence. For some individuals there is a desire to avoid transitioning through puberty to avoid being perceived as the “wrong” gender. Puberty may prompt some individuals to report their gender incongruence to their parents, health care providers, and others.
      • Rosenthal S.M.
      Approach to the patient: transgender youth: endocrine considerations.
      The presentation of gender incongruence during this period of development may be prompted by pressures to conform to societal norms with respect to gender conformity.
      The origins of gender incongruence have focused on psychosocial issues and early traumas to include dysfunctional family dynamics or childhood sexual abuse as being contributory. The original theories practiced by psychologists such as John Money argued that “the norms we raise our children in will dictate their behavior and expressed gender.”
      • Money J.
      The concept of gender identity disorder in childhood and adolescence after 39 years.
      Money and colleagues conducted a study enrolling males with either congenital abnormalities of the penis or a boy who had lost his penis in a surgical accident and raised these individuals as female following treatment with surgery and hormones. In at least one of Money’s cases, the subject committed suicide ostensibly due to the stress endured by living with gender incongruence.
      • Money J.
      • Norman B.
      Gender identity and gender transposition: longitudinal outcome study of 24 male hermaphrodites assigned as boys.
      A more recent theory of gender identity focuses on the that concept biological/gender imprinting occurs early in embryogenesis and development and is not a result of trauma.
      • Reiner W.
      • Gearhart J.
      Discordant sexual identity in some genetic males with cloacal exstrophy assigned to female sex at birth.
      ,
      • Meyer-Bahlburg H.F.L.
      Gender identity outcome in female-raised 46,XY persons with penile agenesis, cloacal exstrophy of the bladder, or penile ablation.
      In fact, there are data suggesting genetics may be involved in the development of gender identity as evidenced by studies in monozygotic twin pairs. Monozygotic twins show a higher concordance of transgender identity than dizygotic twin pairs.
      • Reiner W.
      • Gearhart J.
      Discordant sexual identity in some genetic males with cloacal exstrophy assigned to female sex at birth.
      ,
      • Heylens G.
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      • et al.
      Gender identity disorder in twins: a review of the case report literature.
      Additionally, there are data showing increased rates of transgender identity in children with congenital adrenal hyperplasia (CAH) who were exposed to excess androgen levels in utero.
      • Mazur T.
      Gender dysphoria and gender change in androgen insensitivity or micropenis.
      More data are needed to explore the biological basis of gender identity.

      Are There Environmental/Gene/Programming Interactions Which Influence Gender Identity?

      Intrinsic and environmental cues can modify molecular signals and gene expression patterns through epigenetics whereby interactions between genetic and environmental conditions create a phenotype.
      • Martin-Subero J.
      How epigenomics brings phenotype into being.
      Specifically, microRNAs (miRNAs) are a class of noncoding RNAs which have the ability to post-transcriptionally modify gene expression and influence almost every aspect of physiology, including embryogenesis, metabolism, growth, and development. miRNAs are both enriched and regulated by X chromosome–linked genes.
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      Influence of sex differences on microRNA gene regulation in disease.
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      • Sosa E.
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      Escape of X-linked miRNA genes from meiotic sex chromosome inactivation.
      There is also a sexual dimorphism with respect to the influence of miRNAs on gene expression patterns.
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      ,
      • Dai R.
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      Sexual dimorphism of miRNA expression: a new perspective in understanding the sex bias of autoimmune diseases.
      While our knowledge of miRNAs as epigenetic regulators has significantly increased, only a few studies have focused on their role in mediating and/or influencing sexual identity.
      • Fagegaltier D.
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      A genome-wide survey of sexually dimorphic expression of Drosophila miRNAs identifies the steroid hormone-induced miRNA let-7 as a regulator of sexual identity.
      One area where epigenetics and miRNAs may influence gender identity is during a window of brain development when the body and genitals develop in the direction of one sex and the brain develops in the direction of the opposite sex.
      • Bao A.M.
      • Swaab D.F.
      Sexual differentiation of the human brain: relation to gender identity, sexual orientation and neuropsychiatric disorders.
      This is biologically possible because there is a time frame in which sex hormone imprinting during prenatal development could be influenced by miRNAs causing a dimorphism between the brain and testes/gonads.
      The brain is a sexually dimorphic tissue. Men and women differ with respect to total brain volume, which is larger in men than in women even when corrected for body size.
      • Smith E.S.
      • Junger J.
      • Derntl B.
      • Habel U.
      The transsexual brain—a review of findings on the neural basis of transsexualism.
      Brain sexual dimorphism is thought to be due to differences in expression of brain sex hormone receptors. Specifically, there are regions in the male brain that have higher levels of expression of the androgen receptors, such as the amygdala, than in females. There are also regions in the female brain with a higher density of estrogen receptors, such as the hippocampus.
      • Smith E.S.
      • Junger J.
      • Derntl B.
      • Habel U.
      The transsexual brain—a review of findings on the neural basis of transsexualism.
      The differences in the brain have been thought to be due to organizational effects of fetal testosterone; however, there are now data suggesting differences based on sex may arise before the onset of testosterone production.
      • Lentini E.
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      • Savic I.
      Sex differences in the human brain and the impact of sex chromosomes and sex hormones.
      There are specific genes located on the X and Y chromosomes which have direct genetic effects giving rise to the sexually dimorphic brain, and it is possible miRNAs could influence these genes during developmental windows.
      There are now studies in transgender individuals suggesting that their brain activity, size, and connectivity differs from cisgender individuals. Specifically, transgender individuals’ brain patterning is more consistent with people of their self-experienced gender than their natal sex.
      • Simon L.
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      Regional grey matter structure differences between transsexuals and healthy controls—a voxel based morphometry study.
      ,
      • Steensma T.D.
      • Kreukels B.P.
      • de Vries A.L.C.
      • Cohen-Kettenis P.T.
      Gender identity development in adolescence.
      Zubiaurre-Elorza and colleagues used magnetic resonance imaging (MRI) to examine the brains of female-to-males and male-to-female transgender people — both before and after treatment with cross-sex hormones — and found that even before cross-hormone treatment, the brain structures of the transgender people were more similar to the brains of their experienced gender than those of their natal sex.
      • Zubiaurre-Elorza L.
      • Junque C.
      • Gomez-Gil E.
      • Guillamon A.
      Effects of cross-sex hormone treatment on cortical thickness in transsexual individuals.
      The investigators went on to show that these differences became even more pronounced after cross-hormone therapy.
      • Guillamon A.
      • Junque C.
      • Gomez-Gil E.
      A review of the status of brain structure research in transsexualism.
      There are additional studies delving into the brains of transgender individuals using functional MRI. In a study conducted by psychologist Burke and biologist Bakke, they examined the response to androstadienone, an odorous steroid with pheromone-like properties that causes a sexually dimorphic response in the hypothalamus of men versus women, in 39 prepubertal and 41 adolescent boys and girls with gender incongruence. The researchers found that those individuals with gender incongruence responded similarly to peers of their experienced gender; these findings were noteworthy because the test looked at sex differences in response to odor which is not influenced by societal norms.
      • Burke S.
      • Cohen-Kettenis P.
      • Veltman D.
      • Klink D.
      • Bakker J.
      Hypothalamic response to the chemo-signal androstadienone in gender dysphoric children and adolescents.
      In another study, Burke et al
      • Burke S.M.
      • Menks W.M.
      • Cohen-Kettenis P.T.
      • Klink D.T.
      • Bakker J.
      Click-evoked otoacoustic emissions in children and adolescents with gender identity disorder.
      used a different measurement of brain function by determining the responses of individuals with gender dysphoria to a click-evoked otoacoustic emissions test. In this study, they found transgender men responded similar to how cisgender females would; whereas, transgender females also responded more like cisgender females.
      • Burke S.M.
      • Menks W.M.
      • Cohen-Kettenis P.T.
      • Klink D.T.
      • Bakker J.
      Click-evoked otoacoustic emissions in children and adolescents with gender identity disorder.
      Although there are but a few studies focusing on discordance between natal sex and gender identity, these studies suggest differences in brain phenotypes for transgender people even before hormonal therapy at puberty and provide potential evidence for the role of prenatal organization of the brain in the development of gender identity. Sexual dimorphisms of the brain are thought to be due to fluctuating hormones during puberty, the menstrual cycle, menopause, or hormone replacement therapy. Cross-hormone therapy in transgender individuals appears to have similar influences on aspects of brain morphology/function as shown by trans masculine individuals where cortical thickness increases under treatment with testosterone, whereas estrogen and anti-androgen treatment in trans feminine individuals is associated with a decrease in cortical thickness.
      • Zubiaurre-Elorza L.
      • Junque C.
      • Gomez-Gil E.
      • Guillamon A.
      Effects of cross-sex hormone treatment on cortical thickness in transsexual individuals.
      It is intriguing to speculate that gender identity may have origins during development; however, there are some studies which refute this and suggest that brains of transgender individuals are more similar to those of their shared natal sex. In a study conducted by the Netherlands Institute for Neuroscience, the distribution of gray matter was compared between 55 female-to-male and 38 male-to-female transgender adolescents to those of age-matched cisgender individuals.
      • Hoekzema E.
      • Schagen S.
      • Kreukels B.
      • et al.
      Regional volumes and spatial volumetric distribution of gray matter in the gender dysphoric brain.
      The researchers focused on the hypothalami and the cerebellum; they compared the structure between transgender and cisgender individuals and found no differences in these brain regions by their measurements. One could argue that these areas of the brain are not sexually dimorphic with respect to size, but do differ with respect to sex steroid receptor expression, an area not investigated in this study.
      Inconsistent findings comparing the brains of transgender and cisgender individuals may be due to a myriad of confounding variables which include small sample size and statistical power. Where there is not yet a preponderance of evidence to support a biological basis for a transgender brain, it is important to appreciate that the sense of gender emerges from a host of factors to include biological as well as cultural/societal, all of which may be additive and are challenging to probe. However, with both the increase in visibility of transgender people and the advent of new molecular and biological techniques, now is the time to begin to recruit and encourage transgender individuals to participate in research in an attempt to power studies appropriately and allow researchers to begin to unravel the origins of gender identity. We are certainly not advocating this as a therapeutic approach, but it is now possible, through genetic recombination, to transfer Y chromosome genes to X chromosomes, resulting in people with XX chromosomes who have male characteristics. We point this out to indicate that we are in an age where novel biological techniques could be used in a scientific/research environment for the sole purpose of exploration into the origins of gender identity. One example of how these scientific methods could be used would be to determine if there is an intersection between genetics and epigenomics that influences gender identity.

      Is Gender Influenced by Societal Norms and/or Are There Biological Factors Which Explain the Basis for Gender Incongruence?

      To begin to shed some light on gender identity, children such as Jack in the case study above have been noted to insist before societal influence that their gender identity does not conform to their biological sex. In fact, data suggest the biological underpinnings of gender identity are present at birth, yet the mechanisms for these characteristics are unknown.
      • Saraswat A.
      • Weinand J.D.
      • Safer J.D.
      Evidence supporting the biologic nature of gender identity.
      ,
      • Safer J.D.
      • Tangpricha V.
      Out of the shadows: it is time to mainstream treatment for transgender patients.
      There are data suggesting that gender expression, sexual orientation, and gender identity are not solely influenced by societal norms. In a study of nonhuman primates given a toy-preference test, the animals exhibited toy preferences similar to stereotypical male and female humans; specifically, the male monkeys preferred guns and cars whereas female monkeys preferred plush toys.
      • Alexander G.M.
      • Hines M.
      Sex differences in response to children’s toys in nonhuman primates (Cercopithecus aethiops sabaeus).
      ,
      • Hassett J.M.
      • Siebert E.R.
      • Wallen K.
      Sex differences in rhesus monkey toy preferences parallel those of children.
      These data imply that toy preference in nonhuman primates occurs without societal influence. In studies in females with CAH (females with higher circulating androgen levels), they tended to prefer toys selected by males when compared with their non-CAH sisters.
      • Nordenström A.
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      Sex-typed toy play behavior correlates with the degree of prenatal androgen exposure assessed by CYP21 genotype in girls with congenital adrenal hyperplasia.
      These data imply that circulating sex hormones influence toy selection and, by extension, may influence gender expression independently of societal influences.
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      Emotional and behavioral adjustment in 4 to 11-year-old boys and girls with classic congenital adrenal hyperplasia and unaffected siblings.

      Prevalence of People With Gender Incongruence

      Society is changing and there are now increasing numbers of people who self-identify as gender nonbinary, gender nonconforming, and transgender individuals. In the transgender population, there are approximately 1.4 million people in the United States, or about 0.6% percent of the population, who self-identify as transgender people.
      • Flores A.R.
      • Herman J.L.
      • Gates G.J.
      • Brown T.N.T.
      How Many Adults Identify as Transgender in the United States? Los Angeles, CA: The Williams Institute.
      Another study of more than 28,000 adults found that there was an incidence rate of 1 in 215 people who identified themselves as transgender individuals.
      • Conron K.J.
      • Scott G.
      • Stowell G.S.
      • Landers S.J.
      Transgender health in Massachusetts: results from a household probability sample of adults.
      Additional studies focusing on gender diversity have found that as many as 1 in every 100 people are born intersex, and a study conducted by the Williams Institute at the UCLA School of Law reported that approximately 9 million Americans identified as lesbian, gay, bisexual, or transgender. Lastly, a more recent study found the incidence of transgender-related diagnoses increased from 936 diagnoses in 2009 to 2567 diagnoses in 2013 within the Veterans Health Administration.
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      Access to care for transgender veterans in the Veterans Health Administration: 2006–2013.
      These numbers might not accurately reflect the actual number of individuals who identify as gender different from male or female because neither the US Census Bureau nor the Centers for Disease Control and Prevention provide the opportunity for people to identify themselves as being a gender different from their birth certificate.
      The importance of accurately defining sex and gender even extends to organizations such as the International Olympic Committee (IOC). The IOC attempted to define male and female using binary terms due to their concern that individuals who define themselves as female but have male sex chromosomes might have competitive advantages in women’s events. In an attempt to standardize testing procedures to differentiate men from women, the IOC in the 1960s performed genital exams as well as DNA tests to check for the presence of a Y chromosome. The IOC has subsequently changed their classification and criteria of male and female because they found exceptions to their definitions such as females with XY chromosomes who had female characteristics due to the fact these individuals lacked the ability to respond to endogenous androgens. Additionally, the IOC developed rules as to how to classify females who were born with CAH who had excessively high levels of androgens.
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      • Drop S.L.J.
      Gender dysphoria and gender change in chromosomal females with congenital adrenal hyperplasia.

      Gender Identity Presents Challenges to the Health Care System

      The increasing prevalence of individuals not conforming to stereotypical gender identities provides a challenge to the health care system and access to appropriate health care services.
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      Demographic characteristics and health status of transgender adults in select US regions: Behavioral Risk Factor Surveillance System, 2014.
      Although there is a trend and a movement to increase acceptance of gender nonconforming people, there is still a gap in understanding how best to meet their health care needs. Gender nonconforming and transgender persons report a lack of knowledgeable health care providers, which reportedly leads to suboptimal care and increased rates of certain types of cancer, substance abuse, mental health conditions, infections, and chronic diseases.
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      • Jaffee K.D.
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      Barriers to health care for transgender individuals.
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      Historically, health care for transgender individuals has been limited to very few facilities; there is an ever-pressing need to enhance access to medically and culturally competent care. Members of the medical community, especially medical students, are asking to be educated on how to provide competent care to gender diverse individuals. Lastly, there is an underappreciated challenge in capturing gender identity on documents such as birth certificates. Unfortunately, this problem will initially need to be addressed by country-, state/province-, and or county/parish-specific means as laws and regulations differ. Medical personnel would likely be enlisted to help with these tasks and will need to learn about nuances and regulations posed by each of the governmental agencies.

      The Importance for Future Research

      Understanding the biological and societal factors contributing to gender identity is integral to the safe, effective, and dignified health care for the transgender population, and is critically important in aiding people such as Jack to affirm their gender identity. Individuals who differ from societal norms with respect to gender face cruelty, rejection, and psychological challenges. There are unfortunate statistics reflecting the stress encountered by transgender individuals indicating that 41% of transgender individuals have attempted suicide.
      • Haas A.P.
      • Rodgers P.L.
      • Herman J.L.
      Suicide Attempts among Transgender and Gender Non-Conforming Adults. Findings of the national transgender Discrimination survey. The Williams Institute.
      In an attempt to alleviate the societal stress impacting transgender individuals, it is imperative that the medical community help patients and parents recognize that sex and gender do not need to conventionally fit into what is now perceived as the norm.
      Access to gender-affirming medical care is often unobtainable due to cost and insurance discrimination. Even for individuals with insurance, health plans often outright ban coverage of transition-related care, forcing transgender people to pay outrageous out-of-pocket expenses for medically necessary procedures that are covered without question for non-transgender individuals. More recently, approximately 20 states now provide insurance for transgender care, with coverage details influenced by recommendations from established medical societies. The Patient Protection and Affordable Care Act mandated transgender care nationwide. Many US insurance companies require a clinical diagnosis for reimbursement of transgender medical and surgical interventions, yet the only codes for a transgender diagnosis in the International Classification of Diseases, 10th Revision (ICD-10) are in the mental health section.
      Coverage for Transition Related Health Care.
      Because transgender identity does not always equate with a mental health condition, there is a tentative plan for ICD-11 to add gender incongruence to the sexual health section and remove gender dysphoria entirely, which has established treatment guidelines which are not entirely based on empirical evidence.
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      • et al.
      Endocrine treatment of transsexual persons: an Endocrine Society clinical practice guideline.
      Specifically, little is known about the long-term health and metabolic consequences of gender-affirming cross-sex hormone therapy. Yet, many transgender individuals seek hormone therapy as part of the transition process. Cross-sex hormone therapy has been shown to have positive physical and psychological effects on the transitioning individual and is considered a mainstay treatment for many patients.

      Conclusion

      Given the prevalence of individuals who identify as gender nonconforming and transgender people, now is the time to focus on the origins of gender identity. If a biological definition of gender identity is developed, it is possible there will be a reduction in discriminating practices towards gender nonconforming and transgender individuals. When patients are alienated by health care professionals due to lack of understanding, they are denied basic quality health care. This not only happens at the doctor-patient level, but occurs throughout the medical field. Therefore, it is our hope that enhancing knowledge of all aspects contributing to gender identity will improve the quality and availability of care for all individuals who differ from the classical binary definitions of gender.

      Supplemental Online Material

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