Causes
Low sexual desire alone is not equivalent to HSDD because of the requirement in HSDD that the low sexual desire causes marked distress and interpersonal difficulty and because of the requirement that the low desire is not better accounted for by another disorder in the DSM or by a general medical problem. It is therefore difficult to say exactly what causes HSDD. It is easier to describe, instead, some of the causes of low sexual desire.In men, though there are theoretically more types of HSDD/low sexual desire, typically men are only diagnosed with one of three subtypes. Lifelong/generalised: The man has little or no desire for sexual stimulation (with a partner or alone) and never had. Acquired/generalised: The man previously had sexual interest in his present partner, but lacks interest in sexual activity, partnered or solitary. Acquired/situational: The man was previously sexually interested in his present partner but now lacks sexual interest in this partner but has desire for sexual stimulation (i.e. alone or with someone other than his present partner. )Though it can sometimes be difficult to distinguish between these types, they do not necessarily have the same cause. The cause of lifelong/generalized HSDD is unknown. In the case of acquired/generalized low sexual desire, possible causes include various medical/health problems, psychiatric problems, low levels of testosterone or high levels of prolactin. One theory suggests that sexual desire is controlled by a balance between inhibitory and excitatory factors. This is thought to be expressed via neurotransmitters in selective brain areas.
Some cultures try hard to restrain sexual desire. Others try to excite it. Concepts of "normal" levels of sexual desire are culturally dependent and rarely value-neutral. In the 1970s, there were strong cultural messages that sex is good for you and "the more the better". Within this context, people who were habitually uninterested in sex, who in previous times may not have seen this as a problem, were more likely to feel that this was a situation that needed to be fixed. They may have felt alienated by dominant messages about sexuality and increasingly people went to sex-therapists complaining of low sexual desire. It was within this context that the diagnosis of ISD was created.In the revision of the DSM-III, published in 1987 (DSM-III-R), ISD was subdivided into two categories: Hypoactive Sexual Desire Disorder and Sexual Aversion Disorder (SAD). The former is a lack of interest in sex and the latter is a phobic aversion to sex. In addition to this subdivision, one reason for the change is that the committee involved in revising the psychosexual disorders for the DSM-III-R thought that the term "inhibited" suggests psychodynamic cause (i.e., that the conditions for sexual desire are present, but the person is, for some reason, inhibiting their own sexual interest). The term "hypoactive sexual desire" is more awkward, but more neutral with respect to the cause. The DSM-III-R estimated that about 20% of the population had HSDD.