从TPOAb阳性值探讨妊娠期甲状腺功能正常取值范围
Investigation of the normal ranges of thyroid function indexes based on the TPOAb positive value

目的 ·通过自身抗体阳性值探讨妊娠期甲状腺功能指标的正常取值范围。方法 ·以730名孕妇为研究对象，应用电化学发光法测定促甲状腺激素（TSH）、血清游离三碘甲状原氨酸（FT3）、游离甲状腺素（FT4）、甲状腺过氧化物酶抗体（TPOAb）和甲状腺球蛋白抗体（TGAb），并通过正常取值范围分为低、中、高值组，分析TPOAb、TGAb阳性率的差异。结果 ·妊娠早、中、晚各期TSH的正常低、中、高值3个区组间TPOAb阳性率比较，差异均具有统计学意义；两两比较结果显示，TSH的正常高值水平较正常低值、中值水平更易出现TPOAb的异常。妊娠早期正常TSH值与TPOAb阳性值之间具有明显的正相关性（r=0.661，P=0.038）。结论 ·妊娠各期TSH在正常高值水平，更易出现TPOAb的异常，从而为甲状腺功能指标正常取值范围的确定提供思路；临床中需加强孕妇甲状腺功能和自身抗体的筛查和随访，避免不良妊娠结局。
： Objective · To investigate the normal ranges of thyroid function indexes in pregnancy through the positive values of autoimmune antibodies. Methods · 730 pregnant women were recruited. Levels of serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TGAb) were measured with chemiluminescence immunoassay. The values of each index in the normal ranges were assigned to the respective low, medium, and high groups. The differences in the positive rates of TPOAb and TGAb between groups were analyzed. Results · The differences in the positive rate of TPOAb between TSH low, medium, and high groups in each trimester of pregnancy were statistically significant. Comparison between groups showed that the TSH high group was more likely to develop abnormal TPOAb level than TSH low and medium groups. There was a significant positive correlation between the normal TSH value and the TPOAb positive value in first trimester of pregnancy (r=0.661, P=0.038). Conclusion · The high TSH level in normal range is more likely to be associated with abnormal TPOAb level in each trimester of pregnancy, which provides an idea for determine the normal ranges of thyroid function indexes. Screening and follow-up for thyroid function and autoimmune antibodies of pregnant women should be enhanced to avoid adverse pregnancy outcomes