Whether abnormal thyroid hormone levels have any effect on pregnancy should be analyzed, usually abnormal thyroid hormone levels may have an effect, while abnormal thyroid antibodies usually have a smaller effect. In different hospitals, the specific indicators of the 5 thyroid function tests are different, usually including thyroid hormone indicators FT3, FT4, TSH, some hospitals, the other two are total T3, total T4, and in some hospitals, certain antibodies to the thyroid gland, such as antibodies to the enzyme peroxidase of the thyroid gland and antibodies to the thyroglobulin. Abnormal hormone levels in the 5 indicators of thyroid function, whether it is hyperthyroidism manifested by elevated FT3, FT4 and lowered TSH, or hypothyroidism caused by lowered FT3, FT4 and elevated TSH, may have an impact on the development of the fetus, and may increase the risk of preterm delivery, miscarriage and fetal developmental malformations. Abnormal changes in thyroid-related antibodies are of greater significance in the diagnosis of thyroid dysfunction, but have less direct effect on the fetus and usually do not require medication for intervention. When abnormalities of the 5 thyroid functions are present in the clinic, it is important to go to both endocrinology and obstetrics for evaluation.