Method specific second-trimester reference intervals for thyroid-stimulating hormone and free thyroxine.
OBJECTIVE
To determine second trimester reference intervals for TSH and FT4.


METHODS
Samples from 3102 subjects were tested for TPO and Tg antibodies.


METHODS
Elecsys E170 reference intervals for TSH and FT4 were determined using antibody-negative samples.


RESULTS
Second trimester reference intervals for TSH and FT4 were 0.18-4.07 mIU/L and 9.5-15.8 pmol/L, respectively. The Elecsys E170 TSH results were positively biased compared to ARCHITECT i2000(SR) results for these same samples.


CONCLUSIONS
Method-specific reference intervals are required for TSH and FT4.
Silvio
Rechelle
R
Department of Clinical Laboratory Sciences, Weber State University, Ogden, UT, USA.
Swapp
Karly J
KJ
La'ulu
Sonia L
SL
Hansen-Suchy
Kara
K
Roberts
William L
WL
D005260:Female; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000378:metabolism*; D012015:Reference Standards; D013972:Thyrotropin / Q000378:metabolism*; D013974:Thyroxine / Q000378:metabolism*
D013972:Thyrotropin; D013974:Thyroxine