Dizziness is a common symptom during pregnancy. In the light case, the head is heavy and the feet are light, and the walking is unsteady; in the heavy case, the eyes are black, and the fainting suddenly occurs. Dizziness in pregnant women is often caused by a variety of diseases. Dizziness is a normal reaction to pregnancy, but if the frequency of dizziness is high and getting more and more serious, you need to go to the hospital to avoid adverse effects. What is the cause of dizziness in pregnant women? Dizziness is mainly caused by insufficient blood supply to the brain. 1, low blood pressure, cerebral ischemia This type of pregnant women usually fainted when they suddenly stand up or take the elevator. In the early and middle stages of pregnancy, due to the formation of the placenta, blood pressure has a certain degree of decline, generally lower than usual 1.33-2.67 kPa, which is physiological. Pregnant women with pre-existing hypertension will experience an even greater drop in blood pressure. Blood pressure drops, the flow of blood to the brain will be reduced, resulting in insufficient blood supply to the brain, so that the brain is ischemia and hypoxia, thus causing dizziness. 2. Eating too little Low blood sugar This type of pregnant women sometimes have episodes of dizziness, accompanied by palpitations, fatigue, cold sweat, usually occurring in the case of eating less. During pregnancy, they eat less because of the pregnancy reaction – vomiting. Eating less makes the blood sugar low. Blood sugar is the raw material for the production of energy in muscle cells and brain cells. Low blood sugar, cellular energy that is reduced, which leads to weakness, dizziness, cold sweat, palpitations and other discomforts. 3, improper position, pressure on blood vessels This type of pregnant women generally lying on their backs or lying on the sofa watching TV when the attack, and in the side lying or standing will not have an attack. The dizziness of this type of pregnant women belongs to the supine syndrome. The late stage of pregnancy due to uterine enlargement, lying on the back or lying down when sitting, the heavy uterus pressed on the inferior vena cava behind it, so that the blood in the lower half of the body can not return to the heart; back to the heart to sharply reduce the volume of blood, the heart beat volume is reduced, resulting in a reduction in the supply of blood to the heart and brain, causing dizziness, chest tightness and other discomforts. 4, anemia occurs in pregnant women, is also a common cause of dizziness in pregnant women. Normally, pregnant women should consume iron-rich foods, such as animal blood, pig liver, lean meat and so on. Once anemia occurs, should be urgent iron supplementation, pregnant women also sometimes have dizziness, headache symptoms. If the condition further develops into pre-eclampsia, it can cause convulsions and coma, endangering the life of the pregnant woman and the fetus. This is the most serious complication of pregnancy and should be diagnosed and treated early.