High thyroid stimulating hormone in pregnancy may be caused by physiologic changes in pregnancy, the presence of iodine deficiency, thyroid disorders, and so on. 1. Physiological changes: Thyroid function will undergo physiological changes during pregnancy, resulting in slightly higher than normal thyroid stimulating hormone. 2. Iodine deficiency: the need of pregnant women and fetus for iodine increases after pregnancy. If pregnant women do not pay attention to iodine supplementation in their diets, there will be insufficient raw materials for synthesizing thyroid hormones, resulting in high thyroid stimulating hormones. 3. Thyroid disease: If the pregnant woman has thyroid disease in the past, she will also have symptoms of high thyrotropin. Once a pregnant woman develops high thyroid stimulating hormone, she should go to the hospital in time and be treated under the guidance of the doctor.