The six classes of Sexual Disorders are as follows: 1) sexual desire disorders, 2) sexual arousal disorders, 3) orgasm disorders, 4) sexual pain disorders, 5) sexual dysfunction of any of the four preceding types, but either substance-induced or due to some medical condition, and 6) paraphilias (such as fetishes).
[In addition, see Gender Identity Disorders.]
The majority of sexual dysfunctions and disorders start in young adulthood or in adolescence, if that is when the individual becomes sexually active.
Most people wait a long time to seek help, if they do at all. Treatment includes psychotherapy, sex therapy, and medical approaches, including everything from pharmacotherapy (although sexual dysfunction is many times caused by medication prescribed for other disorders or illness) to surgery.