Causes for spider veins on the face include rosacea, that can be triggered by various factors like, use of alcohol, spicy foods and exposure to sunlight. Other causes include long term use of steroid creams and outdoor work for a prolonged period. Causes for spider veins on the legs include obesity, standing for longer periods, pregnancy, and leg injury. In some people, the condition may develop on the chest, due to chest bruises, chronic cough and cirrhosis of the liver.