Pan Li-Hsin, Yeh Chang-Ching, Yang Shun-Jie, Yang Chen-Chang, Hwu Chii-Min, Chen Harn-Shen, Wang Fan-Fen, Huang Chun-Jui
Division of Endocrinology and Metabolism, Department of Medicine, Zhongxiao Branch, Taipei City Hospital, Taipei, 115006, Taiwan.
Department of Obstetrics & Gynecology, Taipei Veterans General Hospital, Taipei, 11217, Taiwan.
J Endocrinol Invest. 2025 Aug 11. doi: 10.1007/s40618-025-02651-z.
Precise thyroid function assessment during pregnancy prevents inaccurate diagnosis of thyroid disease. This study aimed to establish trimester-specific reference intervals for thyroid function tests (TFTs) in Taiwanese pregnant women and analyze thyroid hormone and anti-thyroid antibody changes through gestation.
This prospective study at Taipei Veterans General Hospital (2019-2022) included 209 pregnant women. After excluding those with positive anti-thyroid antibodies, use of thyroid-related medications, or plans for abortion, 123 participants were eligible for thyroid function reference interval analysis. TFTs including thyroid-stimulating hormone (TSH), free T4, total T4, free T3, and total T3 along with antibodies were measured once per trimester using a Roche electrochemiluminescence immunoassay. One spot urine sample from each woman was collected at baseline to ensure iodine adequacy and urinary iodine concentration was measured by inductively coupled mass spectrometry.
The median urinary iodine concentration was 162.5 µg/L, indicating that the analyzed population had sufficient iodine status. TSH levels were significantly lower in the first trimester (0.007-3.08 µIU/mL) compared to the second (0.33-4.55 µIU/mL) and third trimesters (0.29-4.64 µIU/mL) (p < 0.001). Levels of free T4 and free T3 decreased consistently throughout pregnancy (p < 0.001), while total T3 levels remained stable. In contrast, total T4 levels, anti-thyroid peroxidase antibody titers, and the proportion of women with positive anti-thyrotropin receptor antibodies were higher in the first trimester compared to the second and third trimesters.
This study underscores the importance of trimester-specific, population-based reference intervals for TFTs using the Roche assay and represents the first investigation in Taiwanese populations.
孕期精确的甲状腺功能评估可防止甲状腺疾病的误诊。本研究旨在建立台湾孕妇甲状腺功能测试（TFTs）的孕龄特异性参考区间，并分析孕期甲状腺激素和抗甲状腺抗体的变化。
这项在台北荣民总医院进行的前瞻性研究（2019 - 2022年）纳入了209名孕妇。在排除抗甲状腺抗体阳性、使用甲状腺相关药物或有流产计划的孕妇后，123名参与者符合甲状腺功能参考区间分析的条件。使用罗氏电化学发光免疫分析法在每个孕龄期测量一次TFTs，包括促甲状腺激素（TSH）、游离T4、总T4、游离T3和总T3以及抗体。在基线时收集每位女性的一份晨尿样本以确保碘充足，并通过电感耦合质谱法测量尿碘浓度。
尿碘浓度中位数为162.5 μg/L，表明分析人群的碘状态充足。与孕中期（0.33 - 4.55 μIU/mL）和孕晚期（0.29 - 4.64 μIU/mL）相比，孕早期TSH水平显著更低（0.007 - 3.08 μIU/mL）（p < 0.001）。整个孕期游离T4和游离T3水平持续下降（p < 0.001），而总T3水平保持稳定。相比之下，孕早期总T4水平、抗甲状腺过氧化物酶抗体滴度以及抗促甲状腺素受体抗体阳性女性的比例高于孕中期和孕晚期。
本研究强调了使用罗氏检测法建立孕龄特异性、基于人群的TFTs参考区间的重要性，并且是台湾人群中的首次调查。
