高原地区西藏林芝市妊娠早期特异性甲状腺功能正常参考值范围的建立

Establishment of Trimester-specific Reference Range for Thyroid Hormones During Early Pregnancy inLinzhi,APlateau Region

目的:建立林芝市正常孕妇妊娠早期(孕≤12周)特异性甲状腺功能参考值范围,为高原地区妊娠妇女甲状腺疾病防治提供参考依据。方法:按美国国家临床生化研究院标准,收集2019年1月-2020年6月在林芝市人民医院产前检查的正常妊娠早期(孕≤12周)妇女460例,检测其血清促甲状腺激素(TSH)、游离三碘甲腺原氨酸(FT_(3))和游离甲状腺素(FT_(4)),纳入401例同期育龄非妊娠健康女性为正常对照;采用百分位数(P_(2.5)-P_(97.5))建立妊娠早期TSH、FT_(4)、FT_(3)的正常参考值范围。结果:研究组妊娠早期TSH的参考值范围为0.49-3.70mIU/L,FT_(4)为12.10-21.86 pmol/L,FT_(3)为3.40-6.05 pmol/L;研究组妊娠早期TSH和FT_(4)的中位数与正常对照组比较,差异有统计学意义(P<0.05)。以TSH>4.0 mIU/L作为亚临床甲状腺功能减退症(亚临床甲减)的诊断标准,591名妊娠妇女患病率为2.7%,而以此研究TSH参考值为标准,患病率为5.7%。结论:高原地区妇女妊娠早期甲状腺激素水平与非妊娠妇女存在显著差异;其妊娠早期TSH控制目标可能需要控制得较平原地区更低,以减少孕期甲状腺疾病的漏诊与误诊率。

Objective:Toexplore the earlytrimester-specific reference intervals ofthyroid hormonesin normal pregnant womeninLinzhi,Tibet.Methods:A total of 460 normal early-pregnancy(≤12 weeks)women who visited the Linzhi People's Hospital between January 2019 and June 2020 were recruited according to the National Academy of Clinical Biochemistrycriteria.Blood samples were collectedand the serum TSH,FT_(4)and FT_(3)levels were detected.Meanwhile,401cases of non-pregnant healthy women of childbearing age were selected as controls.The percentile(P_(2.5)~P_(97.5))was employed to indicate the reference ranges of TSH,FT_(4)and FT_(3)in early-pregnancy period.Results:During early pregnancy,the reference intervals of TSH,FT_(4)and FT_(3)were 0.49-3.70 mIU/L,12.10-21.86 pmol/L and 3.40-6.05 pmol/L respectively.Median concentration of trimester-specific TSH and FT_(4)were significantly different from the control group(P<0.05).The prevalence of subclinical hypothyroidism in 591 pregnant women was 2.7% with the diagnostic criterion of TSH 4.0 mIU/L and 5.7%with the upper limit of reference intervals derived in this study.Conclusion:The thyroid hormones' levels during early pregnancy of women in high altitude areas are significantly different from those of non-pregnant women.The earlytrimester-specific TSH level may need to be controlled lower than that in plain areas to reduce the missed and misdiagnosed rate of thyroid diseases during pregnancy.