Hyperthyroidism in pregnancy is commonly associated with Graves’ disease of pregnancy and transient thyrotoxicosis in pregnancy, and diagnostic criteria need to be combined with laboratory findings and other factors.
First, early pregnancy serum thyrotropin levels below the lower limit of the pregnancy-specific reference range (or 0.1 mU/L) suggest the possibility of thyrotoxicosis, and thyroid hormone levels as well as thyroid peroxidase antibodies and thyrotropin receptor antibodies need to be measured.
Transient thyrotoxicosis in pregnancy is associated with overproduction of human chorionic gonadotropin during pregnancy and overstimulation of thyroid hormone production, and the extent of the disease is related to the level of human chorionic gonadotropin. As the weeks of gestation increase, the thyroid function will gradually return to normal, and no medication is usually needed.
Transient thyrotoxicosis in pregnancy is usually not associated with positive antibodies to thyroid peroxidase or thyroid stimulating hormone receptors, but it is associated with elevated thyroid hormones in the blood.
Graves’ disease in pregnancy usually has a family history of autoimmune disorders, thyrotropin receptor antibody tests are mostly positive, accompanied by proptosis and goiter, thyroid enlargement is seen on thyroid ultrasound, and the patient has preexisting hypermetabolic symptoms before pregnancy.
It should be noted that iodine 131 uptake rate and radionuclide scanning tests are contraindicated during pregnancy. Patients suspected of having hyperthyroidism in pregnancy should go to the hospital and ask their doctor to make a judgment.