Reference intervals for common thyroid function tests, during different stages of pregnancy in Chinese women.

Background: The importance of diagnosis of thyroid dysfunction during pregnancy has been widely recognized. Our study was designed to compare two different detection reagents between Abbott and Roche and to establish the gestational related reference intervals for thyroid function tests (TFT) in Chinese women and to assay the reference ranges with the American Thyroid Association recommended standard.

Methods: Serum samples were collected from 693 normal pregnant Chinese women and divided into five groups according to their gestational age: 9-13, 16-20, 24-28, 32-34 and 37-40 weeks.