Thyroid and Pregnancy

Abstract Hormonal changes and metabolic needs during pregnancy result in profound changes in biochemical parameters of thyroid function, especially if there is preexsisting autoimmune thyroid disease (AITD). Normal thyroid function is important in order to ensure the best outcome. Many changes in the functioning of the thyroid gland occur during pregnancy, and some diseases of thyroid gland can affect both mother and fetus. Hypothyroidism is the most serious disorder that occurs during pregnancy and can go unnoticed as a „non-specifi c” problem. Hypothyroidism arises from the reduced ability of the gland to adapt to the increased needs during pregnancy. Mild thyroid dysfunction of mothers in the fi rst trimester, which does not threaten during the pregnancy, can damage the psychomotor development of the child. Measurement of TSH is the most practical, simple and cost- eff ective screening test for thyroid dysfunction. It is necessary to apply the trimester-specifi c TSH reference values to correctly interpreted thyroid function during pregnancy. Th e presence of TPOAb is confi rmation of existence of AITD, and predicts increased risk of developing subclinical hypothyroidism (SH). Preconceptional education and adequate diagnosis and treatment of thyroid dysfunction in early pregnancy are of great importance, in order to prevent complications during pregnancy and off spring. Current data indicate an increase in pregnancy loss, gestational diabetes, gestational hypertension, pre-eclampsia and preterm delivery in women with SH in pregnancy. Th e control of thyroid disease reduce complications of pregnancy.