Men and woman, with some sexually arousing stimulus, proceed through orgasm and end with a return of the body to a sexually unstimulated state. This is described in four stages: Excitement, Plateau, Orgasm, and Resolution. There is no sharply defined moments when one stage ends and the next begins. Each phase merges with the next phase.
- Erection of penis, marked increase in its size, and a rise in its angle. Erection may be triggered by penis itself or by sexually stimulating sight, smell or thought. It occurs in 3 to 8 seconds.
- A small penis may double in length, while in a large penis lengthening is less marked.
- Partial elevation and increase in the size of testes.
Full erection of penis. Increase in size and full elevation of testes. Little secretion from Cowper’s glands appears at the Urethral meatus.
Orgasm occurs in two distinct stages. In the first stage the Vas deferens, the prostate and Seminal vesicles begin a series of contractions that forces semen into the bulb of the urethra. The man experiences a sensation of ‘Ejaculatory inevitability –the feeling of having reached brink of control. At this point ejaculation cannot be stopped. In the second stage of orgasm contraction of urethra and penis combined with contraction in the prostate to cause ejaculation (spurting of semen out of tip of penis). During ejaculation the neck of the urinary bladder is tightly shut to avoid any mixture of semen and urine. The rhythmic contractions of prostate, the perineal muscles and the penis occur initially at 0.8 seconds intervals.
Male orgasm and ejaculation are not one and the same process. Although the two occur simultaneously, orgasm refers to muscular contraction and release of sexual tension, while ejaculation refers to the release of semen. Orgasm without ejaculation is common in boy before puberty.
Man is not able to have multiple orgasms. Immediately after the ejaculation man enters a ‘refractory period’ during which further orgasm or ejaculation is impossible. Usually the erection subsides quickly. There is grate variability in the duration of refractory period. It may last from few minutes to many hours. This period gets longer with each repeated ejaculation. As the man gets older, the refractory period gets longer. The period of return to the unaroused state is called the ‘resolution phase’. The anatomical and physiological changes that occurred during excitement and the plateau phase reverse. Blood is pumped out of penis and therefore loss of erection. The testes decrease in size and descend in scrotum.