Maternal thyroid stimulating hormone levels during the first trimester of pregnancy at the south-east of the Caspian sea in Iran

This study was designed to explore the status of the thyroid stimulating hormone [TSH] in the first trimester of pregnancy. In this analytical research, 'Project 120', apparently healthy pregnant women in their first trimester of pregnancy were selected randomly from pregnant women who visited the Danesh Medical Diagnostic Laboratory in Gorgan, which is located in northern Iran, during 2007-08. Serum TSH was measured by the Enzyme linked Immunosorbant Assay [ELISA]. He findings of this study indicated that 10% of pregnant women who also were apparently healthy subjects showed abnormal TSH serum concentration on the bases of the reference range of the laboratory kit used in this study, which seems to be incorrect. It is concluded here, that for the accurate measurement and the interpretation of thyroid hormones, the proper reference intervals in each region should be established to avoid confusion about the diagnosis of the thyroid function tests.