ABSTRACT
The interpretation of thyroid function tests in pregnancy requires knowledge of iodine metabolism in the nonpregnant female and of the changes in iodine metabolism which accompany pregnancy. The object of clinical assessment of thyroid status is to decide whether the physiological action of the thyroid gland in a patient is reduced, normal, or increased. The final diagnosis is based on a combination of clinical observations and laboratory tests. The standard selection of thyroid function tests includes a simple measurement of radioiodine uptake as a percentage of the administered radioactive dose. Stimulation and suppression tests of thyroid function are based on the normal physiological control of the thyroid gland by the pituitary and hypothalamus. In thyroid diseases, autoantibodies may be produced either to the thyroid colloid or to the thyroid microsomes. The initial requirement in pregnancy is for a rapid screening test to confirm the clinical diagnosis of thyroid status.
