What will cause varicose veins? Varicose veins are mainly because of weakened or broken valves inside the veins, resulting in blood pooling as well as veins turning into swollen and twisted. Pregnancy: Greater blood volume throughout pregnancy supports the increasing newborn but may enlarge the veins in the legs. ramzi https://www.sgvascularctr.com/varicose-vein-treatment-in-singapore-everything-you-need-to-know/