Heredity, or genetic transmission from family, is perhaps the most important risk factor for varicose veins. If varicose veins are present in the family, the likelihood of developing them is between 45% and 90%. Varicose veins are four times more common in women than in men. Pregnancy and obesity, birth control pills, and hormone therapies also increase susceptibility to varicose veins. Therefore, when these factors combine, the risk is significantly increased in women who have been pregnant and have a family history of varicose veins. Each pregnancy further increases the risk, both due to hormonal effects and the significant strain on the body.

Another risk factor is prolonged periods of inactivity, whether standing or sitting. The risk of developing varicose veins is 2.7 times higher in individuals who stand for more than four hours a day. Historically, varicose veins were associated with specific professions such as teachers, flight attendants, dentists, and surgeons due to the prolonged standing required in these jobs. However, the modern work environment, with hours spent at a computer in office settings, has now put almost everyone at risk. While all risks seem more prominent in women, men who live sedentary lives in modern office environments and lack exercise habits are also at risk. It is important to remember that genetic predisposition also applies to men.

Epidemiological studies have highlighted numerous factors playing a role in the pathophysiology of varicose veins. These studies show family history (heredity), risky lifestyles, and smoking as leading risk factors, as they were found at higher rates in patients with diagnosed venous insufficiency. Patients with a positive family history have a 4.4 times greater risk of developing varicose veins. Prolonged standing or sitting is a risk factor; standing for more than four hours a day increases the risk of developing high-grade venous insufficiency by 2.7 times.

Risk factors include:

* Prolonged standing
* Pregnancy
* Obesity
* Sedentary work
* Inactivity
* Old age
* Medication use (Birth control pills, hormone replacement therapy during menopause)