Changes in the sexual desires of any partner in a sexual relationship, if sustained and unresolved, may cause problems in the relationship.
Other causes include experience of sexual abuse, assault, trauma, or neglect, body image issues and anxiety about engaging in sexual activity.
Physical factors that can affect libido include endocrine issues such as hypothyroidism, the effect of certain prescription medications (for example flutamide), and the attractiveness and biological fitness of one's partner, among various other lifestyle factors.
These factors can include lack of privacy or intimacy, stress or fatigue (medical), distraction or depression.
Environmental stress, such as prolonged exposure to elevated sound levels or bright light, can also affect libido.
This cycle has been associated with changes in a woman's testosterone levels during the menstrual cycle.
According to Gabrielle Lichterman, testosterone levels have a direct impact on a woman's interest in sex.
Sexual desires are often an important factor in the formation and maintenance of intimate relationships in humans.
A lack or loss of sexual desire can adversely affect relationships.
It is this need to conform to society and control the libido that leads to tension and disturbance in the individual, prompting the use of ego defenses to dissipate the psychic energy of these unmet and mostly unconscious needs into other forms. A primary goal of psychoanalysis is to bring the drives of the id into consciousness, allowing them to be met directly and thus reducing the patient's reliance on ego defenses.