Establishment Of Trimester-specific Reference Intervals For Thyroid Tests Detcted By Beckman Assay

Objective: To establish the trimester-specific reference intervals forthyroid testing in pregnant women.Methods:589normal pregnant women and118normal nonpregnantwomen were recruited in our hospital The2.5th and97.5th percentiles werecalculated as the reference intervals for dedication serum TSH、FT4、FT3levels during each trimester.Results:(1)in the first、second、third trimester TSH is1.42（0.13,3.99）、1.81（0.47,4.86）、1.91(0.58,5.51)uIU/ml；FT4is0.81（0.63,1.23）、0.63（0.44,0.82）、0.58（0.44,0.80）ng/dl。(2)In addition to TSH level in thesecond trimester had no significant difference compared with thirdtrimester,there were statistical significant differences in TSH、FT4、FT3level in each trimester.Compared with normal women,TSH decreased in thefirst trimester and began to rise in the second trimester.FT4increased in thefirst trimester and reduced gradually in the second trimester.FT3had noobvious change in the first trimester and reduced gradually in the secondtrimester.Conclusion： It is necessary to establish trimester-specific referenceintervals for thyroid tests.