Varicose Vein Causes in Women
Many different events during pregnancy can cause problems with women's veins.
Hormones during pregnancy
Women are more likely to get varicose veins because the hormones progesterone and estrogen cause the veins to dilate. Vein walls have smooth muscle cells just like there are in the uterus. When a woman is pregnant, the hormones relax those smooth muscles, which can cause veins to get bigger.
Within the veins, one-way valves are supposed to keep the blood heading up toward the heart. If those valves are pulled apart because the veins are dilating, the blood can go in the wrong direction, which puts too much pressure on the veins lower in the leg causing them to fail too.
Blood flow obstruction
If a woman has an enlarged uterus from having a baby laying on the veins, it creates a high blood pressure in the veins. The blood can't get out of the legs because the baby in their abdomen is laying on the vena cava, which is largest vein in their abdomen, and this obstructs blood flow.
Increase of blood volume
When a woman is pregnant, her blood volume increases by at least 30 percent. This increased volume stretches the veins out too.