How are they caused?

Heredity is the number one contributing factor causing varicose and spider veins. Women are more likely to suffer from varicose veins, and more than 50 percent of American women with varicose veins experience varying degrees of discomfort as a result.

Hormonal factors such as puberty, pregnancy, menopause and the use of birth control pills and Estrogen also contributes to the disease. As many as 70-80 percent of pregnant women develop varicose veins during the first trimester. Pregnancy causes an increase in hormone levels and blood volume which in turn causes veins to enlarge. In addition, the enlarged uterus causes increased pressure on the veins. Approximately 60-70 percent of varicose veins due to pregnancy will disappear within about three months after delivery.