What Causes Varicose Veins?

Heredity is the number one contributing factor causing varicose and spider veins. Women are more likely to suffer from abnormal leg veins, with up to 50 percent of American women affected. Hormonal factors, including puberty, pregnancy, menopause, use of birth control pills, estrogen, and progesterone all affect the disease. It is very common for pregnant women to develop varicose veins during the first trimester of their pregnancies. Increased hormone levels and blood volume during pregnancy cause the veins to enlarge. In addition, the enlarged uterus causes increased pressure on the veins. Fortunately, varicose veins caused by pregnancy often improve within three months of delivery. However, with successive pregnancies, abnormal veins are more likely to remain.

Other predisposing factors include aging, occupations that require standing for long periods of time, obesity, and leg injury.