Hypothyroidism-a clinical syndrome caused by prolonged, persistent lack of thyroid hormones in the body or lower their biological effects on cm level. Prevalence manifestnogo primary hypothyroidism in a population of 0, 2, 1%, latent primary hypothyroidism 7 - 10% of women and 2 to 3% of men. Over 1 year 5% of latent hypothyroidism goes into manifestny. Pathogenetic hypothyroidism classified as follows : * Primary (tireogenny) * Secondary (gipofizarny) * Tertiary (gipotalamichesky) * Tkanevoy (transport, peripheral) The severity of the primary hypothyroidism are divided into : 1. Latent (subklinichesky) - the highest levels of TTG at normal T4. 2. Manifestny - hypersecretion TTG, and a reduced level T4, clinical manifestations. A. Kompensirovanny. B. Dekompensirovanny. 3. Heavy currents (complicated). There is a serious disease, such as cretinism, cardiac insufficiency, vypot in seroznye cavities, secondary pituitary adenoma. In the vast majority of cases, is the primary hypothyroidism. Most primary hypothyroidism developed in the outcome of autoimmune tireoidita, less frequently, after POE thyroid gland and radioactive 131I therapy.