Lifestyle factors

The below factors may play a part in the development of varicose and spider veins:

Heredity – There is a significant relationship between heredity and the development of varicose veins and spider veins.
Age – The development of varicose veins and spider veins may occur at any age but usually occurs between the ages of 18 and 35 years, and peaks between 50 and 60 years.
Gender – Females are affected approximately four to one to males.
Pregnancy – Pregnancy is a common factor contributing to the formation of varicose and spider veins. The most important factor is circulating hormones that weaken vein walls. There is also a significant increase in the blood volume during pregnancy. This tends to distend veins, causing valve dysfunction which leads to blood pooling in the veins. Additionally, later in pregnancy, the enlarged uterus can compress veins, causing higher vein pressure leading to dilated veins. Varicose veins that form during pregnancy may spontaneously improve or even disappear a few months after delivery.
Lifestyle/Occupation – People who are involved with prolonged sitting or standing in their daily activities have an increased risk of developing varicose veins. Thus, the weight of the blood continuously pressing against the closed valves causes them to fail, leading to distention in the veins.