Unlike westerm medicine, 3 fingers are used to check the pulse rate. The difference between each pulse beat felt on each finger can tell many things. For example, it would be normal if the middle finger feels the most pressure. And the pulse strength can also tell whether the person is having too much heat or cold.
Both wrists are checked because each wrist will tell a different story. The left wrist is said to be connected with some parts of the body, like the kidney yin and liver, whereas the right wrist is connected to the kidney yang, stomach and some other organs.
Traditional Chinese Medicine: Pulse Diagnostics -- powered by eHow.com