Abstract: Thyroid dysfunction is particularly common during pregnancy,it is affect pregnancy outcomes,andthreat maternal and child health.Following the 2011 American Thyroid Association (ATA) release pregnancy thyroid-stimulating hormont(TSH) diagnostic guidelines, In 2012,Endocrinology branch and Perinatal Medicine Branchof the Chinese Medical Association jointly issued the "pregnancy and postpartum thyroid disease diagnosis and treatment guidelines", it is important that each laboratory has its own reference interval for diagnosing thyroid disorders in pregnancy. This article provides an overview of researching and establishing serumtrimester-specific thyroid hormone reference during pregnancy all through the world, and discussing trimester-specific thyroid hormone reference of the area in where the auther live.

Key words: pregnancy , thyroid hormone , reference values