Common causes of swollen limbs: 1. idiopathic swelling, some people may have swollen limbs due to prolonged standing or prolonged sitting, which can generally be relieved after rest; 2. some women may have obvious swelling before menstruation, which may be closely related to elevated hormone levels; 3. kidney disease, when the glomerular filtration rate decreases, it will cause water and sodium retention; 3. Patients with kidney disease often have proteinuria, and long-term proteinuria can lead to hypoproteinemia, which can aggravate swelling; 4. Patients with liver disease often lead to a decrease in synthetic protein, and hypoproteinemia in the body can cause swelling; 5. Patients with heart disease such as heart failure often cause impaired blood return, which can lead to swelling of the extremities; 6, Physiological swelling, swelling often occurs in pregnant women, which is normal, because pregnant women will have a significant increase in blood volume and the enlarged uterus during pregnancy will lead to obstruction of blood return.