Research has shown that paraphilias are rarely observed in women. However, there have been some studies on females with paraphilias. Sexual masochism has been found to be the most commonly observed paraphilia in women, with approximately 1 in 20 cases of sexual masochism being female.

Many acknowledge the scarcity of research on female paraphilias. The majority of paraphilia studies are conducted on people who have been convicted of sex crimes. Since the number of male convicted sex offenders far exceeds the number of female convicted sex offenders, research on paraphilic behavior in women is consequently lacking. Some researchers argue that an underrepresentation exists concerning pedophilia in females. Due to the low number of women in studies on pedophilia, most studies are based from "exclusively male samples". This likely underrepresentation may also be attributable to a "societal tendency to dismiss the negative impact of sexual relationships between young boys and adult women". Michele Elliott has done extensive research on child sexual abuse committed by females, publishing the book "Female Sexual Abuse of Children: The Last Taboo" in an attempt to challenge the gender-biased discourse surrounding sex crimes. John Hunsley states that physiological limitations in the study of female sexuality must also be acknowledged when considering research on paraphilias. He states that while a man's sexual arousal can be directly measured from his erection (see penile plethysmograph), a woman's sexual arousal cannot be measured as clearly (see vaginal photoplethysmograph), and therefore research concerning female sexuality is rarely as conclusive as research on men.

GID exists when a person suffers discontent due to gender identity, causing them emotional distress. Researchers disagree about the nature of distress and impairment in people with GID. Some authors have suggested that people with GID suffer because they are stigmatized and victimized; and that, if society had less strict gender divisions, transsexual people would suffer less.

A twin study (based on seven people in a 314 sample) suggested that GID may be 62% heritable, indicating the possibility of a genetic influence or prenatal development as its origin, in these cases.

Symptoms of GD in children may include any of the following: disgust at their own genitalia, social isolation from their peers, anxiety, loneliness and depression. According to the American Psychological Association, transgender children are more likely to experience harassment and violence in school, foster care, residential treatment centers, homeless centers and juvenile justice programs than other children.

Adults with GD are at increased risk for stress, isolation, anxiety, depression, poor self-esteem and suicide. Studies indicate that transgender people have an extremely high rate of suicide attempts; one study of 6,450 transgender people in the United States found 41% had attempted suicide, compared to a national average of 1.6%. It was also found that suicide attempts were less common among transgender people who said their family ties had remained strong after they came out, but even transgender people at comparatively low risk were still much more likely to have attempted suicide than the general population. Transgender people are also at heightened risk for certain mental disorders such as eating disorders.

Sexual maturation disorder is a disorder of anxiety or depression related to an uncertainty about one's gender identity or sexual orientation. The World Health Organization (WHO) lists sexual maturation disorder in the ICD-10, under "Psychological and behavioural disorders associated with sexual development and orientation".

Sexual orientation, by itself, is not a disorder and is not classified under this heading. It differs from ego-dystonic sexual orientation where the sexual orientation or gender identity is repressed or denied.

Ego-dystonic sexual orientation is an ego-dystonic mental disorder characterized by having a sexual orientation or an attraction that is at odds with one's idealized self-image, causing anxiety and a desire to change one's orientation or become more comfortable with one's sexual orientation. It describes not innate sexual orientation itself, but a conflict between the sexual orientation one wishes to have and the sexual orientation one actually possesses.

Gender identity is a concept, specifically psychological, that refers to one's sense of being a male or female in regards to sexual orientation. Individuals who are diagnosed with gender identity disorder are classified as being dissatisfied with their anatomically determined gender.

Gender dysphoria in children or gender identity disorder in children (GIDC) is a formal diagnosis used by psychologists and physicians to describe children who experience significant discontent (gender dysphoria) with their biological sex, assigned gender, or both.

GIDC was formalized in the third revision of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-III) in 1980 and primarily referenced gender non-conforming behaviors. GIDC remained in the DSM from 1980 to 2013, when it was replaced with the diagnosis of "gender dysphoria" in the fifth revision (DSM-5), in an effort to diminish the stigma attached to gender variance while maintaining a diagnostic route to gender affirming medical interventions such as hormone therapy and surgery.

Controversy surrounding the pathologization and treatment of cross-gender identity and behaviors, particularly in children, has been evident in the literature since the 1980s. Proponents of more widespread GIDC diagnoses argue that therapeutic intervention helps children be more comfortable in their bodies and can prevent adult gender identity disorder. Opponents say that the equivalent therapeutic interventions with gays and lesbians (titled conversion or reparative therapy) have been strongly questioned or declared unethical by the American Psychological Association, American Psychiatric Association, American Association of Social Workers and American Academy of Pediatrics. The World Professional Association for Transgender Health (WPATH) states that treatment aimed at trying to change a person's gender identity and expression to become more congruent with sex assigned at birth "is no longer considered ethical." Critics also argue that the GIDC diagnosis and associated therapeutic interventions rely on the assumption that an adult transsexual identity is undesirable, challenging this assumption along with the lack of clinical data to support outcomes and efficacy.

Gender identity disorder in children is more heavily linked with adult homosexuality than adult transsexualism. According to limited studies, the majority of children diagnosed with GID cease to desire to be the other sex by puberty, with most growing up to identify as gay or lesbian with or without therapeutic intervention.

Psychosexual disorders can vary greatly in severity and treatability. Medical professionals and licensed therapists are necessary in diagnosis and treatment plans. Treatment can vary from therapy to prescription medication. Sex therapy, behavioral therapy, and group therapy may be helpful to those suffering distress from sexual dysfunction. More serious sexual perversions may be treated with androgen blockers or selective serotonin reuptake inhibitors (SSRIs) to help restore hormonal and neurochemical balances.

Children with persistent GID are characterized by more extreme gender dysphoria in childhood than children with desisting gender dysphoria. Some (but not all) gender diverse / gender independent / gender fluid youth will want or need to transition, which may involve social transition (changing dress, name, pronoun), and, for older youth and adolescents, medical transition (hormonal and surgical intervention). Treatment may take the form of puberty blockers such as Lupron Depot or Leuprolide Acetate, or cross-sex hormones (i.e., administering estrogen to an assigned male at birth or testosterone to an assigned female at birth), or surgery (i.e., mastectomies, salphingo-oophorectomies/hysterectomy, the creation of a neophallus in female-to-male transsexuals, orchiectomies, breast augmentation, facial feminization surgery, the creation of a neovagina in male-to-female transsexuals), with the aim of bringing one’s physical body in line with their felt gender. The ability to transition (socially and medically) are sometimes needed in the treatment of gender dysphoria.

The Endocrine Society does not recommend endocrine treatment of prepubertal children because clinical experience suggests that GID can be reliably assessed only after the first signs of puberty. It recommends treating transsexual adolescents by suppressing puberty with puberty blockers until age 16 years old, after which cross-sex hormones may be given.

The University of Washington is leading the largest study of transgender youth ever conducted. The study, known as the Transgender Youth Project, looks at 300 transgender kids between the ages of 3 and 12. Researchers hope to follow the children for 20 years.

In the United States, following a series of landmark cases in the Supreme Court of the United States, persons diagnosed with paraphilias, particularly pedophilia ("Kansas v. Hendricks", 1997) and exhibitionism ("Kansas v. Crane", 2002), with a history of anti-social behavior and related criminal history, can be held indefinitely in civil confinement under various state legislation generically known as sexually violent predator laws and the federal Adam Walsh Act ("United States v. Comstock", 2010).

There are many ways a person may go about receiving therapy for ego-dystonic sexual orientation associated with homosexuality. There is no known therapy for other types of ego-dystonic sexual orientations. Therapy can be aimed at changing sexual orientation, sexual behaviour, or helping a client become more comfortable with their sexual orientation and behaviours. Human rights groups have accused some countries of performing these treatments on egosyntonic homosexuals. One survey suggested that viewing the same-sex activities as compulsive facilitated commitment to a mixed-orientation marriage and to monogamy. Treatment may include sexual orientation change efforts or treatment to alleviate the stress. In addition, some people seek non-professional methods, such as religious counselling or attendance in an ex-gay group.

As the disorder progresses in life, it can increase in severity, and cause other behaviors or actions in late adolescence and adulthood. “A strong and persistent cross-gender identification in adolescents and adults [can cause a] disturbance manifested by symptoms such as a stated desire to be the other sex, frequent passing as the other sex, desire to live or be treated as the other sex, or the conviction that he or she has the typical feelings and reactions of the other sex” (APA, 2000). This can cause severe conflict for the individual living in a society which endorses and enforces adherence to strict gender roles. In a more persistent disassociation with one’s own body or gender, someone can go to more extreme lengths to feel as though they are fulfilled or satisfied with themselves. This can lead these individuals to engage in behavior that displaces their emotions. These individuals may also seek to undergo sex reassignment surgery. “Persistent discomfort with his or her sex or sense of inappropriateness in the gender role of that sex in adolescents and adults [can cause a] disturbance manifested by symptoms such as preoccupation with getting rid of primary and secondary sex characteristics (e.g., request for hormones, surgery, or other procedures to physically alter sexual characteristics to simulate the other sex) or belief that he or she was born the wrong sex” (APA, 2000).

Transsexual people experience a gender identity that is inconsistent with, or not culturally associated with, their assigned sex, and desire to permanently transition to the gender with which they identify, usually seeking medical assistance (including hormone replacement therapy and other sex reassignment therapies) to help them align their body with their identified sex or gender.

"Transsexual" is generally considered a subset of "transgender", but some transsexual people reject the label of "transgender". A medical diagnosis of gender dysphoria can be made if a person expresses a desire to live and be accepted as a member of their identified sex, and if a person experiences impaired functioning or distress as a result of their gender identity.

Biphobia is aversion toward bisexuality and toward bisexual people as a social group or as individuals. It can take the form of denial that bisexuality is a genuine sexual orientation, or of negative stereotypes about people who are bisexual (such as the beliefs that they are promiscuous or dishonest). People of any sexual orientation can experience or perpetuate biphobia, and it is a source of social discrimination against bisexual people.

"Sex reassignment therapy" (SRT) is an umbrella term for all medical treatments related to sex reassignment of both transgender and intersex people.

Individuals make different choices regarding sex reassignment therapy, which may include female-to-male or male-to-female hormone replacement therapy (HRT) to modify secondary sex characteristics, sex reassignment surgery (such as orchiectomy) to alter primary sex characteristics, chest surgery such as top surgery or breast augmentation, or, in the case of trans women, a trachea shave, facial feminization surgery or permanent hair removal.

To obtain sex reassignment therapy, transsexual people are generally required to undergo a psychological evaluation and receive a diagnosis of gender identity disorder in accordance with the Standards of Care (SOC) as published by the World Professional Association for Transgender Health. This assessment is usually accompanied by counseling on issues of adjustment to the desired gender role, effects and risks of medical treatments, and sometimes also by psychological therapy. The SOC are intended as guidelines, not inflexible rules, and are intended to ensure that clients are properly informed and in sound psychological health, and to discourage people from transitioning based on unrealistic expectations.

Until the 1990s, it tended to be described mostly as acrotomophilia, at the expense of other disabilities, or of the wish by some to pretend or acquire disability. Bruno (1997) systematised the attraction as factitious disability disorder. A decade on, others argue that erotic target location error is at play, classifying the attraction as an identity disorder. In the standard psychiatric reference "Diagnostic and Statistical Manual of Mental Disorders", text revision (DSM-IV-tr), the fetish falls under the general category of "Sexual and Gender Identity Disorders" and the more specific category of paraphilia, or sexual fetishes; this classification is preserved in DSM-5.

Transmisogyny (sometimes trans-misogyny) is the intersection of transphobia and misogyny. Transphobia is defined as "the irrational fear of, aversion to, or discrimination against transgender or transsexual people". Misogyny is defined as "a hatred of women". Therefore, transmisogyny includes negative attitudes, hate, and discrimination of transgender or transsexual individuals who fall on the feminine side of the gender spectrum, particularly transgender women. The term was coined by Julia Serano in her 2007 book "Whipping Girl" and used to describe the unique discrimination faced by trans women because of "the assumption that femaleness and femininity are inferior to, and exist primarily for the benefit of, maleness and masculinity", and the way that transphobia intensifies the misogyny faced by trans women (and vice versa). It is said many trans women experience an additional layer of misogyny in the form of fetishization; Serano talks about how society views trans women in certain ways that sexualize them, such as them transitioning for sexual reasons, or ways where they’re seen as sexually promiscuous.Transmisogyny is a central concept in transfeminism and is commonly referenced in intersectional feminist theory. That trans women's femaleness (rather than only their femininity) is a source of transmisogyny is denied by certain radical feminists, who claim that trans women are not female.

Attraction to disability or devotism is a sexualised interest in the appearance, sensation and experience of disability. It may extend from normal human sexuality into a type of sexual fetishism. Sexologically, the pathological end of the attraction tends to be classified as a paraphilia. (Note, however, that the very concept "paraphilia" continues to elude satisfactory definition and remains a subject of ongoing debate in both professional and lay communities) Other researchers have approached it as a form of identity disorder. The most common interests are towards amputations, prosthesis, and crutches.

Transmisogyny is generally understood to be caused by the social belief that men are superior to women. In "Whipping Girl", Julia Serano writes that the existence of trans women is seen as a threat to a "male-centered gender hierarchy, where it is assumed that men are better than women and that masculinity is superior to femininity". Gender theorist Judith Butler echoes this assumption, stating that the murder of transgender women is "an act of power, a way of re-asserting domination... killing establishes the killer as sovereign in the moment that he kills".

Trans women are also viewed as threatening the heterosexuality of cisgender men. In media, "deceivers" such as Dil, a transgender woman from the 1992 film "The Crying Game", have been observed to invoke outrage and male homophobia in an audience when their "true" maleness is unveiled.

Transphobia is a range of negative attitudes, feelings or actions toward transgender or transsexual people, or toward transsexuality. Transphobia can be emotional disgust, fear, violence, anger or discomfort felt or expressed towards people who do not conform to society's gender expectations. It is often expressed alongside homophobic views and hence is often considered an aspect of homophobia. Transphobia is a type of prejudice and discrimination similar to racism and sexism, and transgender people of color are often subjected to all three forms of discrimination at once.

Child victims of transphobia experience harassment, school bullying, and violence in school, foster care, and social programs. Adult victims experience public ridicule, harassment including misgendering, taunts, threats of violence, robbery, and false arrest; many feel unsafe in public. A high percentage report being victims of sexual violence. Some are refused healthcare or suffer workplace discrimination, including being fired for being transgender, or feel under siege by conservative political or religious groups who oppose laws to protect them. There is even discrimination from some people within the movement for the rights of gender and sexual minorities.

Besides the increased risk of violence and other threats, the stress created by transphobia can cause negative emotional consequences which may lead to substance abuse, running away from home (in minors), and a higher rate of suicide.

In the Western world, there have been gradual changes towards the establishment of policies of non-discrimination and equal opportunity. The trend is also taking shape in developing nations. In addition, campaigns regarding the LGBT community are being spread around the world to improve acceptance; the "Stop the Stigma" campaign by the UN is one such development.

During the year prior to the 2015 U.S. survey, 59 percent of respondents reported avoiding using a public restroom out of fear of violence or harassment. 32 percent limited the amount they ate or drink in order to avoid using a public restroom. Eight percent reported suffering a urinary tract infection, kidney infection, or other kidney problem as a result of avoiding public restrooms.

Thirty-three percent reported having negative experiences with a healthcare professional related to being transgender, such as verbal harassment or denial of treatment. 23 percent reported that they did not seek treatment for a condition out of fear of being mistreated, while 33 percent did not seek treatment because they were unable to afford it.

During the month prior to the survey, 39 percent of American transgender people experienced major psychological distress, compared to 5 percent of the general population of the United States. 40 percent had attempted suicide at some point in their life, compared to 4.6 percent of the American population. Family and community support were correlated with far lower rates of suicide attempts and of major psychological distress.

A study conducted on transgender women of color in San Francisco has shown a higher correlation between transphobia and risk of transgender women engaging in HIV risk behavior. The study shows that the transgender youth face social discrimination, and they may not have a social role model. The young adults in this group have shown a higher risk of engaging in unprotected receptive anal intercourse when the exposure to transphobia is high. Therefore, as per the study shows a correlation between transphobia and high risk of HIV.

DID is rarely diagnosed in children, despite the average age of appearance of the first alter being three years. This fact is cited as a reason to doubt the validity of DID, and proponents of both etiologies believe that the discovery of DID in a child that had never undergone treatment would critically undermine the SCM. Conversely, if children are found to only develop DID after undergoing treatment it would challenge the traumagenic model. , approximately 250 cases of DID in children have been identified, though the data does not offer unequivocal support for either theory. While children have been diagnosed with DID before therapy, several were presented to clinicians by parents who were themselves diagnosed with DID; others were influenced by the appearance of DID in popular culture or due to a diagnosis of psychosis due to hearing voices—a symptom also found in DID. No studies have looked for children with DID in the general population, and the single study that attempted to look for children with DID not already in therapy did so by examining siblings of those already in therapy for DID. An analysis of diagnosis of children reported in scientific publications, 44 case studies of single patients were found to be evenly distributed (i.e., each case study was reported by a different author) but in articles regarding groups of patients, four researchers were responsible for the majority of the reports.

The initial theoretical description of DID was that dissociative symptoms were a means of coping with extreme stress (particularly childhood sexual and physical abuse), but this belief has been challenged by the data of multiple research studies. Proponents of the traumagenic hypothesis claim the high correlation of child sexual and physical abuse reported by adults with DID corroborates the link between trauma and DID. However, the DID-maltreatment link has been questioned for several reasons. The studies reporting the links often rely on self-report rather than independent corroborations, and these results may be worsened by selection and referral bias. Most studies of trauma and dissociation are cross-sectional rather than longitudinal, which means researchers can not attribute causation, and studies avoiding recall bias have failed to corroborate such a causal link. In addition, studies rarely control for the many disorders comorbid with DID, or family maladjustment (which is itself highly correlated with DID). The popular association of DID with childhood abuse is relatively recent, occurring only after the publication of "Sybil" in 1973. Most previous examples of "multiples" such as Chris Costner Sizemore, whose life was depicted in the book and film "The Three Faces of Eve", disclosed no history of child abuse.

Child molestation, or child sexual abuse, is a form of sexual assault in which a child, an adult or older adolescent abuses a younger child for sexual satisfaction. (Yes, a child CAN molest another child, this is defined as child-on-child sexual abuse). This can include talking to a child about having sex, showing pornography to a child, making a child participate in the production of pornography, exposing genitals to a child, fondling of a child’s genitals, or forcing a child to engage in any form of sexual intercourse. Force is not often used in child molestation. Children usually cooperate because they are not fully aware of the significance of what is happening. They also may feel intimidated by the adult or older adolescent.

Victims of child molestation often experience their feelings about the incidents later in life when they can fully understand the importance. They often feel that their privacy has been invaded when they were too young to consent. They can feel like they were taken advantage of and betrayed by those that they trusted. Victims of child molestation can experience long-term psychological traumas. This pushes them to distrust others. The lack of reliance on others can lead to an overall fear of sexual intercourse.

Rape is the unconsensual and unlawful act of sexual intercourse forced by one person onto another. This can include penetration, but does not have to. Victims of rape can be female or male. “Rape is the most extreme possible invasion of a person’s physical and emotional privacy.” It is considered to be such a heinous crime because victims are attacked in a very personal manner and because physical force or deception can be utilized. Rape can be physically painful, but it can be more emotionally unbearable. Rape is often described as less of an invasion of the body and more of an invasion of “self.” Victims often have intense emotional reactions, usually in a predictable order. This is known as rape trauma syndrome.

Rape victims can experience added stress after the assault because of the way hospital staff, police personnel, friends, family, and significant others react to the situation. They can often feel lowered self-esteem and even a sense of helplessness. They long for a sense of safety and control over their lives. Rape victims can develop a fear of sex for physical and psychological reasons. During sexual assault, victims experience physical trauma such as soreness, bruising, pain, genital irritation, genital infection, severe tearing of vaginal walls, and rectal bleeding. They may also grapple with fear of the potential reoccurrence of assault. This possibility for rape can put stress on relationships as well. Some women and men can become distrusting and suspicious of others. Rape victims can become fearful of sexual intercourse because of physical pain and mental anguish.

The common pathway of sexual differentiation, where a productive human female has an XX chromosome pair, and a productive male has an XY pair, is relevant to the development of intersex conditions.

During fertilization, the sperm adds either an X (female) or a Y (male) chromosome to the X in the ovum. This determines the genetic sex of the embryo. During the first weeks of development, genetic male and female fetuses are "anatomically indistinguishable", with primitive gonads beginning to develop during approximately the sixth week of gestation. The gonads, in a "bipotential state", may develop into either testes (the male gonads) or ovaries (the female gonads), depending on the consequent events. Through the seventh week, genetically female and genetically male fetuses appear identical.

At around eight weeks of gestation, the gonads of an XY embryo differentiate into functional testes, secreting testosterone. Ovarian differentiation, for XX embryos, does not occur until approximately Week 12 of gestation. In normal female differentiation, the Müllerian duct system develops into the uterus, Fallopian tubes, and inner third of the vagina.

In males, the Müllerian duct-inhibiting hormone MIH causes this duct system to regress. Next, androgens cause the development of the Wolffian duct system, which develops into the vas deferens, seminal vesicles, and ejaculatory ducts.

By birth, the typical fetus has been completely "sexed" male or female, meaning that the genetic sex (XY-male or XX-female) corresponds with the phenotypical sex; that is to say, genetic sex corresponds with internal and external gonads, and external appearance of the genitals.