Plateau Phase

In the plateau phase, the accumulation of blood in the genitals reaches a maximum.

The penis increases further in diameter and the colour of the penis may change to a mottled reddish-purple colour. The testes become more elevated so that they are situated tightly against the body. If the testes do not elevate sufficiently, full ejaculatory response does not occur. The testes also increase in size, anywhere from 50-100%. Generally, the longer the individual remains in the plateau stage, the more obvious is the increase in testicular size.

If stimulation continues, a man will enter the plateau phase, which varies in length, depending on the type of stimulation and his own desires. (Many individuals like to prolong this phase with extended "foreplay.") As arousal levels rise, blood pressure, heart rate, respiratory rate and muscle tension also increase. Increased blood flow further enlarges the penis and causes the testicles to swell to approximately 50 percent beyond their normal size. The prostate gland becomes larger. The tiny Cowper's or Bulbourtheral glands release a few drops of pre-ejaculatory fluid, a clear, slippery substance which is secreted from the tip of the penis. Note: pre-ejaculate may also contain some live sperm from a previous ejaculation and can get a woman pregnant. Many men also develop a sex flush (redness of skin), predominantly on the chest.