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The sexual response cycle
Medical expert of the article
Last reviewed: 08.07.2025
Human sexual function is the result of a complex interaction between the autonomic nervous system, which regulates the body's vital functions without conscious control, the vascular system, which is responsible for the blood supply to the genitals, and the endocrine system, which controls the secretion of hormones and their release. These systems operate in close connection with thinking and emotions.
Researchers into sexuality have found that the cycle of sexual responses can be divided into four phases.
Attraction. Sexual arousal can be caused by verbal or physical stimulation, as well as by thinking about it. Sexual fantasies can equally cause arousal and awaken desire, which sets the sexual mechanisms in motion.
Arousal. This is the stage of sexual tension (arousal) and erotic delight. With appropriate stimulation, the parasympathetic nerves cause a significant rush of blood to the genital area. In men, an erection occurs (enlargement of the penis). In women, the vagina and clitoris swell, the vagina becomes moist and slippery. The heartbeat quickens. With continued stimulation, voluptuous tension occurs.
Orgasm. Voluptuous sensations reach their peak in this phase. In men, ejaculation occurs. In women, orgasm manifests itself in a reflexive rhythmic contraction of the muscles surrounding the vagina.
Relaxation. The genitals return to their previous state, the heart rate and breathing rate return to normal.
While a woman is capable of quickly repeating the cycle described above, men are unable to achieve an erection for a certain period of time (from minutes to hours). This period, called the refractory time, increases with age. In young men, this refractory time is often only a few seconds, after 30 years it increases to half an hour, at the age of 50 the refractory period lasts on average from 8 to 24 hours. On the other hand, with increasing age, the time of orgasm in men significantly increases.
Organic or functional factors can cause disturbances in the normal cycle of sexual responses and sexual activity. When such disturbances occur, we can speak of sexual dysfunction.
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