The normal range of thyroid stimulating hormone in pregnant women is divided into three periods. Early pregnancy is between 0.1 and 2.5 uIU/ml, the normal range in mid-pregnancy should be between 0.2 and 3.0 uIU/ml, and late pregnancy should be between 0.3 and 3.0 uIU/ml. The value of thyroid stimulating hormone in pregnant women is not a constant value, but a dynamic indicator of constant change. During pregnancy, if the thyroid stimulating hormone is lowered, there may be a combination of hyperthyroidism, and if the thyroid stimulating hormone is raised, there may be a combination of hypothyroidism. The combination of thyroid disorders in pregnancy may lead to the development of adverse pregnancy outcomes. Therefore, it is important to maintain thyroid function in a normal state prior to pregnancy. When thyroid stimulating hormone is found to be at an abnormal level, seek medical attention and follow medical advice.