Why do spider and varicose veins occur?
Veins most often dilate and become varicose as a result of increased downward pressure on the vein from a point above it. The pressure can be something as temporary as a pregnancy or the straining associated with moving your bowels (both of which increase the abdominal pressure), or as constant as the forces of gravity and your own body weight. Medical studies have found that the composition of a varicosities walls is different from that of normal vein walls thus suggesting something inherently different about varicose veins themselves. Patients often say there is a family history of varicose and spider veins and this most likely will increase ones chances of suffering from them in the future. It is rare but some people are born without the one-way valves that help prevent venous blood from flowing downward instead of upward toward the heart. More commonly however these valves are not functioning correctly as is seen after having suffered a prior phlebitis (blood clot). People who spen
