Establishment of reference range of serum thyroid hormone in women with different gestational age in Wu-han area

CAI Wenqian; HU Xijiang; YAO Ting; CHEN Qi

doi:10.3969/j.issn.1006-5725.2017.24.015

Abstract：Objective To establish the laboratory and geography-specific reference intervals for thyroid hormones during pregnancy and changes of serum thyroid hormone in Wuhan. Methods According to NACB guidelines,a total of 1 186 female including in or without pregnancy were recruited in our hospital randomly when they came to routine antenatal clinic. The 2.5 th and 97.5 th percentiles were calculated as the reference intervals for specialty of serum thyroid function including serum thyroid stimulating hormone(TSH),serum free three io-dine thyroid(FT3),serum free thyroxine(FT4)levels during each trimester by chemiluminescence.Results On comparing to non-pregnant women,the serum thyroid hormone in pregnant women had significant difference as the following:(1)FT3 concentrations showed decreased median centile throughout gestation step by step;(2)FT4 lev-els in second and third trimester had slightly decreased;(3)TSH levels had significant decreased in first and sec-ond trimeste and had no significant difference between the early pregnancy and middle pregnancy,and had recoved to the similar level of before pregnancy in middle pregnancy and late pregnancy.Compared with control group,the serum thyroid function levels of pregnant women had significant differences in trimesters. There were 5.84%, 19.09% and 28.91% of women in the first,second and third trimester,respectively,with serum TSH higher than the upper reference limit,or lower than the lower reference limit.Conclusions Serum thyroid function had signifi-cant correlations with pregnancy in Wuhan area. To establish pregnancy-specific thyroid function reference inter-vals of local area can reduce underdiagnosis effectively in thyroid gland related diseases.