Abstract: Objective To establish the reference range of thyroid hormone at different stages of pregnancy,we analyzed the serum levels of major thyroid markers in healthy women in Wuhu area during pregnancy. Methods A total of 379 women during the different pregnancy were selected to detect TSH,FT3 and FT4 by Chemiluminescence Immunoassay. Another 118 healthy non-pregnant women were selected as control group。Analysis of TSH,FT3,FT4 three indicators in the different stages. Results Serum TSH,FT3,FT4 in the early pregnancy of the reference range were 0.38~4.07 mIU/L,3.55~ 5.30 pmol/L,11.35~17.43 pmol/L. The reference range in the middle of pregnancy was 0.41~4.14 mIU/L,2.99~5.20 pmol/L,10.48~17.79 pmol/L. In the late pregnancy reference range were 0.54~4.54 mIU/L,2.88~4.86 pmol/L,9.27~16.47 pmol/L. Conclusion The main serological indexes of thyroid in healthy pregnant women in Wuhu area were significantly different at different gestational periods,and we should establish a reference range for different pregnancies.

Key words: Pregnancy, Thyroid hormone, Reference range