Sexual dysfunction is generally classified into four types or categories:
Pain disorders
Orgasm disorders (either delay or absence of orgasm)
Desire disorders (lack of interest in sex or of sexual desire)
Arousal disorders (inability to become physically aroused during sexual activity)
For men, symptoms of sexual dysfunction include:
Inability to control the timing of ejaculation, such as early (premature) ejaculation or retarded ejaculation, which is the absence or delay of ejaculation
Erectile dysfunction, or the inability to achieve or maintain an erection hard enough for intercourse
Hormone imbalance is the primary cause of ED and other sexual dysfunctions in men, including low libido, shorter and/or weaker orgasms, low testosterone, or even trouble reaching orgasm.