Varicose veins refer to enlarged veins that are usually found on the thighs, inner thighs, and the back of the calves. They can be red, blue, or flesh-colored, and they are similar in appearance to twisted and bulging cords. In some people, they may swell and protrude from the surface of the skin. Pregnant women may find varicose veins forming around the buttocks or vagina.
In most cases, varicose veins are caused by damaged or weakened venous valves. Your heart distributes oxygenated blood and nutrients throughout your body via the arteries, and the veins transport blood from various parts of your body back to your heart. When the muscles in your legs squeeze, they send blood back to your heart from the lower part of your body, and the blood has to move against the force of gravity. The venous valves function to prevent blood from flowing back to your legs when it is moving upwards. If they are weak or damaged, the blood may leak back into your lower body and accumulate there. This condition is referred to as venous insufficiency, and it can cause your veins to become varicose.
Varicose veins are a very common condition, and they occur in about 50% of people who are aged 50 and above.
Some of the factors that increase your chances of developing varicose veins include increasing age, hormonal changes, medical history, obesity, lack of movement, and pregnancy. Birth control pills and other medications that contain estrogen or progesterone can also contribute to the formation of varicose veins. All these factors can lead to the weakening of venous valves, higher rates of blood flow, or increased pressure on veins, and cause blood to flow back to your lower body.