Psychosexual disorders are disturbances in sexual function secondary to emotional and/or mental causes. This category includes sexual dysfunctions, sexual perversions (paraphilias), and gender identity disorders, and is separate from sexual disorders that may arise from an underlying medical condition.

    Sexual dysfunctions may be characterized as a disturbance of sexual desire, arousal, or orgasm; sexual pain; or difficulties with sexual performance. Causes may be mental or physical, and can result in the individual's inability to fully enjoy sexual intercourse. In men, sexual dysfunctions may manifest as reduced sexual desire, premature or delayed ejaculation, impotence, or painful intercourse. In women, sexual dysfunctions may manifest as reduced sexual desire, inadequate lubrication, difficulty or inability to achieve orgasm, or painful intercourse. Because sexual dysfunctions may be related to a medical condition, medication, or substance abuse, adequate medical workup is imperative before the initiation of treatment.

    Sexual perversions (paraphilias) involve strong and recurrent sexual desire for unusual situations or objects. Examples are displaying one's genitals (exhibitionism); sexual desire for children (pedophilia), non-consenting adults (sexual sadism), objects (fetishism); observing other people unclothed or engaged in sexual activities (voyeurism); rubbing against someone or something for purposes of sexual stimulation (frottage or frotteurism); and cross-dressing (transvestic fetishism). Paraphiliacbehavior usually begins in adolescence.

    Gender identity disorders characterize individuals who desire to be—or insist that they are—members of the other sex. Gender identity disorder symptoms can develop as early as ages 2 to 4. In boys, the cross-gender identification is manifested by a preoccupation with toys, dress and activities that are stereotypically female. Girls identify with the opposite gender in the preoccupation of role-play, dreams and fantasies. However, only a small number of children will continue to have symptoms that meet criteria for this disorder in adolescence or adulthood. In adults, such gender-identification can lead to sex-change operations (sexual reassignment surgery).

    Incidence and Prevalence: The prevalence of painful sex from a sexual dysfunction is distributed among 3% of males and 15% of females. Orgasmic problems are reported by 10% of males and 25% of females. Ten percent of males also report that they have trouble maintaining erections, whereas 20% of females have trouble sustaining arousal (DSM-IV-TR 538, 569, 578).

    The incidence of paraphilias is hard to establish since it is a diagnosis that is difficult to make due to afflicted individuals' reluctance to talk about these sexual concerns. Sexual masochism has a 20:1 male to female ratio. Hypoxyphilia, a form of sexual masochism where, in order to enhance sexual pleasure, individuals deprive themselves of oxygen either with a noose or other means, has a death rate of 2 per 1 million population in US, UK, Canada, and Australia (DSM-IV-TR 527-573). There is no data on the prevalence of gender identity disorder in the US. In Europe 1 per 30,000 males and 1 per 100,000 females see a clinician requesting sexual reassignment surgery