Thyrotropin, TSH, is a hormone that is very important during pregnancy, as high or low levels can easily affect the growth and development of the baby, leading to miscarriage, abnormal fetal development, etc. TSH levels are recommended to be controlled between 0.1-2.5 IU/mL in early pregnancy, 0.2-2.5 IU/mL in mid pregnancy, and 0.2-3.0 IU/mL in late pregnancy. It is recommended to control between 0.2-3.0 IU/mL during late pregnancy. For pregnant women with TSH abnormalities found during pregnancy, it is recommended to have blood tests for thyroid function every 4 weeks. In addition, thyroid antibodies and thyroid ultrasound should be improved. For the judgment and interpretation of these indicators, it is recommended to do so under the guidance of an endocrinologist. For those who have symptoms or whose values are not well controlled, treatment by medication is required.