The prenatal hormonal theory of sexual orientation suggests that people who are exposed to excess levels of sex hormones have masculinized brains and show increased homosexuality or bisexuality. Studies providing evidence for the masculinization of the brain have, however, not been conducted to date. Research on special conditions such as congenital adrenal hyperplasia (CAH) and exposure to diethylstilbestrol (DES) indicate that prenatal exposure to, respectively, excess testosterone and estrogens are associated with female–female sex fantasies in adults. Both effects are associated with bisexuality rather than homosexuality.
The causes of transsexuality have been studied for decades. The most studied factors are biological. Certain brain structures in trans women have been found to be similar to cisgender women's as opposed to cis men's, and trans men's have been found to be similar to cis men's, even controlling for hormone use, which can also cause trans people's brains to become closer to those of cis people of the same gender. However, these studies are limited as they include a small number of tested individuals. Brain structure differences have also been part of extensive research on biology and sexual orientation. Studies have also found that both androphilic and gynephilic trans women's brain function and responses are like cis women's and unlike cis men's, or are intermediate between the two. Likewise, studies such as Rametti's have found that trans men have male-like white matter patterns (even before using hormones), regardless of sexual orientation.
In spite of these similarities, these two groups should not be and cannot be thought of as one. The truth is that the vast majority of people with intersex conditions identify as male or female rather than transgender or transsexual. Thus, where all people who identify as transgender or transsexual experience problems with their gender identity, only a small portion of intersex people experience these problems.
Ancient Greek religious texts, reflecting cultural practices, incorporated bisexual themes. The subtexts varied, from the mystical to the didactic. Spartans thought that love and erotic relationships between experienced and novice soldiers would solidify combat loyalty and unit cohesion, and encourage heroic tactics as men vied to impress their lovers. Once the younger soldiers reached maturity, the relationship was supposed to become non-sexual, but it is not clear how strictly this was followed. There was some stigma attached to young men who continued their relationships with their mentors into adulthood. For example, Aristophanes calls them euryprôktoi, meaning "wide arses", and depicts them like women.
Male bisexuality is particularly presumed to be non-existent, with sexual fluidity studies adding to the debate. In 2005, researchers Gerulf Rieger, Meredith L. Chivers, and J. Michael Bailey used penile plethysmography to measure the arousal of self-identified bisexual men to pornography involving only men and pornography involving only women. Participants were recruited via advertisements in gay-oriented magazines and an alternative paper. They found that the self-identified bisexual men in their sample had genital arousal patterns similar to either homosexual or heterosexual men. The authors concluded that "in terms of behavior and identity, bisexual men clearly exist", but that male bisexuality had not been shown to exist with respect to arousal or attraction. The assertion of Bailey that "for men arousal is orientation" was criticized by Fairness and Accuracy in Reporting (FAIR) as a simplification which neglects to account for behavior and self-identification. Further, some researchers hold that the technique used in the study to measure genital arousal is too crude to capture the richness (erotic sensations, affection, admiration) that constitutes sexual attraction. The National Gay and Lesbian Task Force called the study and The New York Times coverage of it flawed and biphobic.
In April 2014, the Supreme Court of India declared transgender to be a 'third gender' in Indian law. The transgender community in India (made up of Hijras and others) has a long history in India and in Hindu mythology. Justice KS Radhakrishnan noted in his decision that, "Seldom, our society realizes or cares to realize the trauma, agony and pain which the members of Transgender community undergo, nor appreciates the innate feelings of the members of the Transgender community, especially of those whose mind and body disown their biological sex", adding:
Some scholars, most notably the Yale professor and historian John Boswell (1947–94), have argued that same-sex unions were recognized by the Roman Catholic Church in medieval Europe, although others have disputed this claim. Scholars and the general public became increasingly interested in the issue during the late 20th century, a period when attitudes toward homosexuality and laws regulating homosexual behaviour were liberalized, particularly in western Europe and the United States.
The Copenhagen Pride festival is held every year in August. In its current format it has been held every year since 1996, where Copenhagen hosted EuroPride. Before 1994 the national LGBT association organised demonstration-like freedom marches. Copenhagen Pride is a colourful and festive occasion, combining political issues with concerts, films and a parade. The focal point is the City Hall Square in the city centre. It usually opens on the Wednesday of Pride Week, culminating on the Saturday with a parade and Denmark's Mr Gay contest. In 2017, some 25,000 people took part in the parade with floats and flags, and about 300,000 were out in the streets to experience it.
Author and journalist Jonathan Rauch has argued that marriage is good for all men, whether homosexual or heterosexual, because engaging in its social roles reduces men's aggression and promiscuity. The data of current psychological and other social science studies on same-sex marriage in comparison to mixed-sex marriage indicate that same-sex and mixed-sex relationships do not differ in their essential psychosocial dimensions; that a parent's sexual orientation is unrelated to their ability to provide a healthy and nurturing family environment; and that marriage bestows substantial psychological, social, and health benefits. Same-sex parents and carers and their children are likely to benefit in numerous ways from legal recognition of their families, and providing such recognition through marriage will bestow greater benefit than civil unions or domestic partnerships.
In 2004, the nation's newly elected Socialist Government, led by President José Luis Rodríguez Zapatero, began a campaign for its legalization, including the right of adoption by same-sex couples. After much debate, the law permitting same-sex marriage was passed by the Cortes Generales (Spain's bicameral Parliament) on 30 June 2005. King Juan Carlos, who by law has up to 30 days to decide whether to grant royal assent to laws, signed it on 1 July 2005. The law was published on 2 July 2005.
Marriage provides both physical and psychological health benefits, and banning gay marriage increases rates of psychological disorders.  The American Psychological Association, American Psychiatric Association, and others wrote in a Sep. 2007 amicus brief, "...allowing same-sex couples to marry would give them access to the social support that already facilitates and strengthens heterosexual marriages, with all of the psychological and physical health benefits associated with that support."  A 2012 study by researchers from UCLA, San Francisco State University, and the University of Massachusetts at Amherst found that same-sex married couples were "significantly less distressed than lesbian, gay, and bisexual persons not in a legally recognized relationship."  A 2010 analysis published in the American Journal of Public Health found that after their states had banned gay marriage, gay, lesbian and bisexual people suffered a 37% increase in mood disorders, a 42% increase in alcohol-use disorders, and a 248% increase in generalized anxiety disorders. 
A transvestite is a person who cross-dresses, or dresses in clothes typically associated with the gender opposite the one they were assigned at birth. The term transvestite is used as a synonym for the term cross-dresser, although cross-dresser is generally considered the preferred term. The term cross-dresser is not exactly defined in the relevant literature. Michael A. Gilbert, professor at the Department of Philosophy, York University, Toronto, offers this definition: "[A cross-dresser] is a person who has an apparent gender identification with one sex, and who has and certainly has been birth-designated as belonging to [that] sex, but who wears the clothing of the opposite sex because it is that of the opposite sex." This definition excludes people "who wear opposite sex clothing for other reasons," such as "those female impersonators who look upon dressing as solely connected to their livelihood, actors undertaking roles, individual males and females enjoying a masquerade, and so on. These individuals are cross dressing but are not cross dressers." Cross-dressers may not identify with, want to be, or adopt the behaviors or practices of the opposite gender and generally do not want to change their bodies medically or surgically. The majority of cross-dressers identify as heterosexual.
The flag was originally created with eight colors, but pink and turquoise were removed for production purposes, and since 1979 it has consisted of six colored stripes. It is most commonly flown with the red stripe on top, as the colors appear in a natural rainbow. Aside from the obvious symbolism of a mixed LGBT community, the colors were determined to symbolize:
In Thailand and Laos, the term kathoey is used to refer to male-to-female transgender people and effeminate gay men. Transgender people have also been documented in Iran, Japan, Nepal, Indonesia, Vietnam, South Korea, Singapore, and the greater Chinese region, including Hong Kong, Taiwan, and the People's Republic of China.
In 2013, Hong Kong's High Court ruled that a transgender woman can marry her boyfriend and told the government that they had one year to draft a law that allows for post-operation transsexual or transgender individuals to marry. In spring of 2014, it was announced that though the law had not been finished, transgender citizens could start marrying in July. Some rights activists have expressed their discontent with the provision that a person must have undergone complete gender reassignment surgery to receive a marriage license. On 17 July 2014, it was announced that transgender citizens could marry and that the law will be finished after the summer recess. Some have stated that the delay of the final draft was a positive thing since the subsequent law has "lots of holes and ambiguity".
Many homosexual and bisexual individuals have a problem with the use of the pink triangle symbol as it was the symbol that Hitler's regime used to tag homosexuals (similar to the yellow Star of David that is constituted of two opposed, overlapping triangles). Because pink triangles were used in the persecution of homosexuals in the Nazi regime, a double moon symbol was devised specifically to avoid the use of triangles. This bisexual symbol is a double moon that is formed when the sex-specific attributes of the astrological symbol of Mars & Venus (representing heterosexual union) are reduced to the two circles open on both ends, thus symbolizing that bisexuals are open to either-sex unions. The color of the bisexual double moon symbol varies. The symbol is most often displayed with rainbow colors, signifying that bisexuals belong to the gay community. It also may appear with the pink-purple-blue colors of the bisexual pride flag. The double moon symbol is common in Germany and surrounding countries.
‘”John” was suicidal. He had been bullied by trolls on social media for most of his life for being different. The bullies were primarily people who claimed, based on their religious beliefs, that “John” was going to hell and deserved to die. They described how they would kill him on his twitter page and people supported their hate. Desperate for help, John sought treatment for his shame, depression, and suicidality. Although he was scared to share about himself with a stranger, he felt desperate for help as he had NO desire to harm anyone, ever. Once he shared about his attraction to children, his therapist told him, “I don’t treat sex offenders,”’ a passage on The Prevention Project about MAPs reads.
On 17 December 2015, the Congress of Nayarit approved a bill legalizing same-sex marriage. In January 2016, the Mexican Supreme Court declared Jalisco's Civil Code unconstitutional for limiting marriage to opposite-sex couples, effectively legalizing same-sex marriage in the state. On 10 May 2016, the Congress of Campeche passed a same-sex marriage bill. On 18 May 2016, both Michoacán and Morelos passed bills allowing for same-sex marriage to be legal. On 25 May 2016, a bill to legalize same-sex marriage in Colima was approved by the state Congress. In July and August 2017, respectively, the Mexican Supreme Court invalidated same-sex marriage bans in the states of Chiapas and Puebla. In November 2017, the State Government of Baja California decided to stop enforcing its same-sex marriage ban.
Some researchers have criticized the conclusions drawn from the study by saying that the measures of sexual arousal were too crude to capture the richness of sexual attraction that includes more than genital and self-reported arousal while watching 2 minute video clips. In a New York Times article, Dr. Gilbert Herdt, director of the National Sexuality Resource Center in San Francisco, was quoted as saying, "To claim on the basis of this study that there's no such thing as male bisexuality is overstepping, it seems to me."
Same-sex marriages are licensed in and recognized by all U.S. states and District of Columbia, as well as all U.S. territories except American Samoa. On July 3, 2015, the Attorney General for American Samoa stated "we are reviewing the opinion [Obergefell v. Hodges] and its potential applicability to American Samoa, and will provide comment when it is completed." Currently same-sex marriages are neither licensed nor recognized there. On January 6, 2016, Alabama's Chief Justice, Roy Moore, issued a ruling forbidding state officials from issuing marriage licenses to same-sex couples. The ruling had no effect as all Alabama counties continued either issuing marriage licenses to all couples or not issue licenses at all. In May 2016 Moore was charged with ethics violations by the state Judicial Inquiry Commission for the ruling, subsequently being suspended from the bench for the remainder of his term on September 30 of that year.
Different religions have their own views about transgender and transsexual individuals, and not all religions are tolerant toward this community. There is no clear distinction of the two terms in religious texts, and, though most religions have condemned trans behavior, there are cultures and traditions that promote acceptance in some parts of the world, religion notwithstanding.
Despite the distinction between sexual orientation and gender, throughout history the gay, lesbian, and bisexual subculture was often the only place where gender-variant people were socially accepted in the gender role they felt they belonged to; especially during the time when legal or medical transitioning was almost impossible. This acceptance has had a complex history. Like the wider world, the gay community in Western societies did not generally distinguish between sex and gender identity until the 1970s, and often perceived gender-variant people more as homosexuals who behaved in a gender-variant way than as gender-variant people in their own right . Today, members of the transgender community often continue to struggle to remain part of the same movement as lesbian, gay, and bisexual people and to be included in rights protections . In addition, the role of the transgender community in the history of LGBT rights is often overlooked, as shown in Transforming History.
On June 8, 2017, the city of Philadelphia adopted a revised version of the flag. The design adds black and brown stripes to the top of the standard six-color flag, "to highlight black and brown LGBTQIA members within the city's community". Some LGBT activists in Philadelphia and other communities criticised the flag as unnecessary and divisive.
As of 24 May 2019, same-sex marriage is legally performed and recognized (nationwide or in some parts) in the following countries: Argentina, Australia, Austria, Belgium, Brazil, Canada, Colombia, Denmark, Finland, France, Germany, Iceland, Ireland, Luxembourg, Malta, Mexico,[a] the Netherlands,[b] New Zealand,[c] Norway, Portugal, South Africa, Spain, Sweden, Taiwan, the United Kingdom,[d] the United States,[e] and Uruguay. Same-sex marriage is also due to become legally performed and recognized in Costa Rica[f]
The degree to which individuals feel genuine, authentic, and comfortable within their external appearance and accept their genuine identity has been called transgender congruence. Many transgender people experience gender dysphoria, and some seek medical treatments such as hormone replacement therapy, sex reassignment surgery, or psychotherapy. Not all transgender people desire these treatments, and some cannot undergo them for financial or medical reasons.
The Parliamentary Library’s chronology of selected polls states that the outcomes of several polls from a variety of groups conducted over the years 2004 to 2010 may suggest a shift in public opinion in favour of same-sex marriage. However, in an August 2013 Fairfax Nielsen Poll, 57% of respondents said that same-sex marriage was ‘not important at all’ in deciding how they would vote in the coming election.
+ UN decl. sign. "Stable unions" legal in some states since 2004; all rights as recognized family entities available nationwide since 2011 Legal in some states since 2012, nationwide since 2013 Legal since 2010  Banned in all Brazilian states; comprehensive nationwide anti-discrimination law pending. Pathologization or attempted treatment of sexual orientation by mental health professionals illegal since 1999 Transgender people can change their legal gender and name before a notary without the need of surgeries or judicial order since 2018
Several studies comparing bisexuals with hetero- or homosexuals have indicated that bisexuals have higher rates of sexual activity, fantasy or erotic interest. Van Wyk and Geist found that male and female bisexuals had more sexual fantasy than heterosexuals. Dixon found that bisexual men had more sexual activities with women than did heterosexual men. Bisexual men masturbated more but had fewer happy marriages than heterosexuals. Bressler and Lavender (1986) found that bisexual women had more orgasms per week and they described them as stronger than those of hetero- or homosexual women. They also found that marriages with a bisexual female were happier than heterosexual unions, observed less instance of hidden infidelity, and ended in divorce less frequently. Goode and Haber found bisexual women to be sexually mature earlier, masturbate and enjoy masturbation more and to be more experienced in different types of heterosexual contact.
One study surveyed more than 1,500 lesbian, gay and bisexual adults across the nation and found that respondents from the 25 states that have outlawed same-sex marriage had the highest reports of "minority stress"—the chronic social stress that results from minority-group stigmatization—as well as general psychological distress. According to the study, the negative campaigning that comes with a ban is directly responsible for the increased stress. Past research has shown that minority stress is linked to health risks such as risky sexual behavior and substance abuse.
In December 2012, the state of São Paulo likewise had same-sex marriage legalized by court order. Same-sex marriages also became equalized in relation to opposite-sex ones between January 2012 and April 2013 by court order in Alagoas, Ceará, Espírito Santo, the Federal District, Mato Grosso do Sul, Paraíba, Paraná, Piauí, Rondônia, Santa Catarina and Sergipe, and in Santa Rita do Sapucaí, a municipality in Minas Gerais. In Rio de Janeiro, the State Court facilitated its realization by district judges in agreement with the equalization (instead of ordering notaries to accept same-sex marriages in demand as all others).
Auckland's City Auckland Pride Festival holds its parade in February every year. In 2018, lesbian couple Victoria Envy and Sinéad O'Connell became the first couple in New Zealand to legally wed in the parade. and Jacinda Ardern became the first New Zealand Prime Minister to walk in the Auckland Pride Parade. In March, Wellington also holds a pride parade during the Wellington Pride Festival.
Ancestral law in ancient Sparta mandated same-sex relationships with youths who were coming of age for all adult men, so long as the men eventually took wives and produced children. The Spartans thought that love and erotic relationships between experienced and novice soldiers would solidify combat loyalty and encourage heroic tactics as men vied to impress their lovers. Once the younger soldiers reached maturity, the relationship was supposed to become non-sexual, but it is not clear how strictly this was followed. There was some stigma attached to young men who continued their relationships with their mentors into adulthood. For example, Aristophanes calls them euryprôktoi, meaning "wide arses", and depicts them like women.
In 1977, Harvey Milk challenged Gilbert Baker, a veteran who taught himself to sew, to come up with a symbol of pride for the gay community. His response? The original Pride flag. Inspired by Judy Garland's "Over the Rainbow," these colors flew at the San Francisco Gay Freedom Day Parade celebration on June 25, 1978. Though some dispute whether Baker was the sole creator of the flag that started it all, its symbolism remains. Each color celebrates an aspect of queer Pride:
^ Jump up to: a b Gay and Lesbian Alliance Against Defamation. "GLAAD Media Reference Guide – Transgender glossary of terms" Archived 2012-06-03 at WebCite, "GLAAD", USA, May 2010. Retrieved 2011-02-24. "An umbrella term for people whose gender identity and/or gender expression differs from what is typically associated with the sex they were assigned at birth."
"Brief of the American Psychological Association, The California Psychological Association, the American Psychiatric Association, and the American Association for Marriage and Family Therapy as amici curiae in support of plaintiff-appellees – Appeal from United States District Court for the Northern District of California Civil Case No. 09-CV-2292 VRW (Honorable Vaughn R. Walker)" (PDF). Retrieved 5 November 2010.
Marriage is a privilege, not a right. The US Constitution contains no explicit right to marry.  The European Court of Human Rights ruled on June 24, 2010 that the state has a valid interest in protecting the traditional definition of marriage, and stated that the Convention for the Protection of Human Rights and Fundamental Freedoms "enshrined the traditional concept of marriage as being between a man and a woman."   Society can choose not to allow same-sex couples to marry, just as it does not allow a person to marry more than one partner or allow minors or close relatives to marry.  Matthew D. Staver, JD, Dean of the Liberty University School of Law, explained: "The unifying characteristics of the protected classes within the Civil Rights Act of 1964 include (1) a history of longstanding, widespread discrimination, (2) economic disadvantage, and (3) immutable characteristics... 'Sexual orientation' does not meet any of the three objective criteria shared by the historically protected civil rights categories."