An adult’s sexuality has seven components: gender identity, orientation, intention (what one wants to do with a partner’s body and have done with one’s body during sexual behavior), desire, arousal, orgasm, and emotional satisfaction. The first three components constitute our sexual identity. The next three comprise our sexual function. The seventh, emotional satisfaction, is based on our personal reflections on the first six.

DSM-IV-TR designates impairments of five of these components as pathologies. Concerns about orientation and the failure to find sexual behaviors emotionally satisfying are not officially considered to be sexual disorders.

DSM-IV-TR specifies three criteria for each sexual dysfunction. The first criterion describes the psychophysiologic impairment; for example, absence of sexual desire, arousal, or orgasm. The second requires that the patient have marked distress or interpersonal difficulty as a result, while the third asks the clinician to ascertain that some other Axis I diagnosis, medical illness, medication, or substances of abuse does not best explain the problem.

The diverse and changeable sexual desire manifestations are produced by the intersection of three mental forces: drive (biology), motive (psychology), and values (culture).

Sexual drive is recognized by genital tingling, heightened responsivness to erotic environmental cues, plans for self or partner sexual behavior, nocturnal orgasm, and increased erotic preoccupations. These are spontaneous particularly among adolescents and young adults. Without drive, the sexual response system is less efficient. While men as a group seem to have significantly more drive than women as a group, in both sexes, drive requires at least the presence of a modest amount of testosterone. Drive is frequently dampened by medications, substances of abuse, psychiatric illness, systemic physical illness, despair, and aging.

The psychological aspect of desire is referred to as motive and is recognized by willingness to bring one’s body to the partner for sexual behavior either through initiation or receptivity. Motive often directly stems from the person’s perception of the context of the nonsexual and sexual relationship. Sexual desire diagnoses are made in people who have adequate drive manifestations and those who apparently have none. Most sexual desire problems in physically healthy adults are generated by one partner’s unwillingness to engage in sexual behavior. This is often kept secret from the partner.

Sexual motives are originally programmed by social and cultural experiences. Children and adolescents acquire values – beliefs, expectations, and rules – for sexual expression. Young people have to negotiate their way through the fact that their early motives to behave sexually frequently coexist with their motives not to engage in sexual behavior. Conflicting motives often persist throughout life but the reasons for the conflict evolve.

Sexual dysfunction refers to sexual expression that is distinguished by a disturbance in the processes that typify the sexual response cycle or by pain associated with sexual intercourse. In other words, disruption of any of the phases of human sexual response results in a sexual dysfunction disorder. These disorders are broken into the following subgroups:

• Desire disorders
  
• Arousal disorders
  
• Orgasmic disorders
  
• Pain disorders.

These disorders can be classified also as either lifelong or acquired, generalized or situational, and caused by psychological factors or combined factors.

29.5.1 Sexual Desire Diagnoses

Two official diagnoses are given to men and women whose desires for partner sexual behavior are deficient: hypoactive sexual desire disorder (HSDD) and sexual aversion disorder (SAD). The differences between the two revolve around the emotional intensity with which the patient avoids sexual behavior. When visceral anxiety, fear, or disgust is routinely felt as sexual behavior becomes a possibility, sexual aversion is diagnosed. HSDD is far more frequently encountered. It is present in at least twice as many women as men; female-to-male ratio for aversion is far higher.

As with all sexual dysfunctions, the desire diagnoses may be lifelong or may have been acquired after a period of ordinary fluctuations of sexual desire. Acquired disorders may be partner-specific (“situational”) or may occur with all subsequent partners (“generalized”).

29.5.2 Arousal Disorders

29.5.2.1 Female Sexual Arousal Disorder

The specificity and validity of female sexual arousal disorder (FSAD) is unclear. In women, it is far more difficult to separate arousal and desire problems than in young men. New desire/arousal problems arise typically in the middle-to-late forties in up to 50% of women as perimenopausal vaginal lubrication diminishes. It is assumed to be endocrine in origin even though estrogen treatment only reliably improves the symptoms relating to vaginal moisture deficiency. The disorder is also seen among regularly menstruating women, who claim that they desire sex but simply do not become aroused with the same efficiency and intensity. Making the diagnosis of FSAD implies that drive and motivation are reasonably intact.

The disorder is typically an acquired one. The women focus on the lack of moisture in the vagina or their failure to be excited by the behaviors that previously reliably brought pleasure. Assuming that some mental factor distracts them from excitement during lovemaking, therapy focuses on identifying what this might be. In menopausal women, FSAD is more often focused on the body as a whole rather than just genital moisture deficiencies.

29.5.2.2 Male Erectile Disorder

Erectile disorder (ED) is characterized by a persistent or recurrent inability to attain, or to maintain until completion of the sexual activity, an erection sufficient for satisfactory sexual performance. While it is widely recognized that young men more commonly have pure psychogenic ED and men over 50 often have significant organic contributants, some younger men have organic factors and some older men have significant psychologic and interpersonal reasons for their inability to sustain potency.

The prevalence of ED rises dramatically in the sixth decade of life from less than 10% to 30%; it increases further during the seventh decade. Aging, medical conditions such as diabetes, prostate cancer, hypertension, and cardiovascular risk factors predict the most common pattern of ED due to a medical condition in this age group. While medication-induced, neurologic, endocrine, metabolic, radiation, and surgical causes of erectile dysfunction also exist, in population studies diabetes, hypertension, smoking, lipid abnormalities, obesity, and lack of exercise are correlated with the progressive deterioration of erectile functioning in the sixth and seventh decades.

29.5.3 Orgasmic Disorders

Men and women exhibit a wide variability in the type or intensity of stimulation that triggers orgasm. These diagnoses should take into account the person’s age, life circumstances, and the adequacy of intensity and duration of the sexual stimulation because these disorders may be caused by psychologic or medical conditions.

Female orgasmic disorder (FOD) and male orgasmic disorder (MOD) are characterized by a persistent or recurrent delay in, or absence of, orgasm after a normal sexual excitement phase. Orgasm is the reflexive culmination of arousal. When a woman can only readily attain orgasm during masturbation, she is diagnosed as having a situational type of FOD. The acquired varieties of this disorder are more common and may present as complete anorgasmia, too-infrequent orgasms, or too-difficult orgasmic attainment. The most common cause of this problem is serotonergic compounds, such as the selective serotonin reuptake inhibitors. The diagnosis of FOD is made when the woman’s psychology persistently interferes with her body’s natural progression through arousal.

When a man can readily attain a lasting erection with a partner, yet is consistently unable to attain orgasm in the body of the partner, he is diagnosed with MOD. The disorder has three levels of severity. The most common form is characterized by the ability to attain orgasm with a partner outside of her or his body, either through oral, manual, or personal masturbation. The more severe form is characterized by the man’s inability to ejaculate in his partner’s presence. The rarest form is characterized by the inability to ejaculate when awake.