Why is the Engagement Ring Worn on the Third Finger of the Left Hand?
It was once believed that the vein of love (vena amoris) ran from this finger directly to the heart. Romantic as this may be, medical science does not support this view. Practically speaking, the third finger is more convenient as a matter of protection for the ring itself, since the first and second are too active. The left hand was chosen for the ring because it normally is less active than the right, hence safer. Approximately 75% of women receive diamond engagement rings before marriage.