Common causes of fainting in pregnant women include postural hypotension, hypoglycemia and anemia in pregnancy. 1. Postural hypotension: Suddenly getting up after lying down or squatting for a long time may lead to insufficient blood supply to the brain, resulting in temporary ischemia of the brain, which may make pregnant women feel dizzy and then faint. 2. Hypoglycemia: In early pregnancy, due to the effect of early pregnancy reaction, pregnant women are prone to loss of appetite, resulting in a decrease in the amount of food intake, which is prone to hypoglycemia and fainting. 3. Anemia during pregnancy: During pregnancy, if anemia caused by various reasons is not corrected in time, it may lead to weakness, dizziness, panic and shortness of breath, and even fainting. If repeated fainting occurs during pregnancy, go to the hospital in time to clarify the cause and treat it actively.