Pregnancy
Restless leg syndrome during pregnancy typically happens in the third trimester. The symptoms are temporary and thought to be due to the hormonal changes [5] that occur during pregnancy or a reduction in serum ferritin levels [6]. Restless leg syndrome associated with pregnancy often phases out after the woman has delivered the child.
Kidney Disease
People with kidney failure or end-stage kidney disease are at a higher risk of developing restless leg syndrome. It is not clear what exactly causes it, but studies show [7] that the risk is greater in people who have undergone dialysis.
This disorder possibly affects patients with kidney failure because of anemia or iron deficiency. The level of iron in the blood may decrease significantly when the kidneys do not function as they should. Other changes in the body caused by kidney failure may also increase your disposition to the syndrome.