There are many causes of low thyrotropic hormone in the body, and the cause needs to be identified before treatment. Low thyroid stimulating hormone is caused by the body’s failure to produce sufficient amounts of thyroid stimulating hormone due to various reasons such as illness. Thyrotropin is a glycoprotein synthesized by the body itself and secreted and released through the pituitary gland. Its main function is to promote the growth and development of the thyroid gland and to regulate the synthesis and secretion of thyroid hormones, as well as to promote the synthesis and secretion of thyroid hormones by the thyroid gland. Among the many causes of low thyroid hormone, the following are more common: 1. early hyperthyroidism. 2. subclinical hyperthyroidism, which is usually purely low thyroid hormone, but not accompanied by an abnormal increase in triiodothyronine and thyroxine. 3. post-thyroid surgery, excessive thyroxine use can also lead to low thyroid hormone. 4. when some 5. If you have hyperthyroidism, during the treatment period, the hyperthyroidism is controlled to a certain degree, but the thyroid hormone level has not yet returned to normal. Low thyroid hormone can affect people’s health, especially children during their growth period, and they need to go to the hospital early for effective treatment.