马鞍山育龄妇女孕早期和孕中期甲状腺激素参考值队列研究

Reference ranges for thyroid hormones among women during 1st and 2nd trimester of pregnancy: a population-based cohort study in Ma'anshan city

目的观察安徽省马鞍山市育龄妇女妊娠早、中期甲状腺功能评估指标的动态变化,建立参考值范围,为临床妊娠期甲状腺功能障碍的诊断提供划界值。方法纳入2013年5月—2014年9月在马鞍山市妇幼保健院开展的前瞻性队列研究中2 378名孕妇,于妊娠≤14周收集基本人口学信息,并于妊娠早期和中期采集孕妇血清进行甲状腺功能相关指标检测。结果妊娠早、中期血清促甲状腺素(TSH)参考值范围分别为0.02~4.94、0.79~6.22 m IU/L。游离甲状腺素(FT_4)的妊娠早、中期参考值分别为13.20~23.85、9.18~15.24 pmol/L。总甲状腺素(TT_4)和总三碘甲状腺原氨酸(TT3)浓度中位数在妊娠6~13周随孕周的增加呈上升趋势,24~28周时趋于稳定。TSH在妊娠早期与中期呈显著正相关(r=0.591,P<0.001),同样,在血清FT_4、TT_4、TT3中也发现了类似的正相关(r分别为0.447、0.537、0.532,P<0.001)。结论妊娠期甲状腺功能相关指标(TSH、FT_4、TT_4、TT3)在妊娠早、中期存在差异并显著关联;建立地区性妊娠期甲状腺激素参考值范围有利于当地妊娠期甲状腺疾病的筛查、诊断和治疗。

Objective To observe dynamic changes in thyroid functional indicators among healthy women during 1st and 2nd trimester of pregnancy in Ma＇anshan city, Anhui province, and to establish a normal reference range of cutoff value for the diagnosis of thyroid dysfunction.Methods From May 2013 to September 2014, a total of 2 378 pregnant women attending the Maternal and Child Health Care Center of Ma＇anshan City for antenatal care were recruited in a cohort. Demographic information of the women were collected before 14 gestational weeks and serum samples were collected during the 1st and 2nd trimester of pregnancy to evaluate thyroid function-related indicators.Results The established reference ranges for thyroid stimulating hormone （TSH） were 0.02-4.94 mIU/L and 0.79-6.22 mIU/L and those for free thyroxine （FT4） were 13.20-23.85 pmol/L and 9.18-15.24 pmol/L, respectively, during the 1st and 2nd trimester of pregnancy. The median value of total thyroxine （TT4） and total triiodothyronine （TT3） were gradually increased with the increment of gestational weeks between the 6th to 13th gestational week and maintained at stable level between 24th and 28th gestational week. A significantly positive correlation was observed between TSH in the 1st trimester and that in the 2nd trimester of pregnancy （r=0.591, P 〈 0.001）. Similar positive associations were found among FT4, TT3 and TT4 during the two semesters of pregnancy （r=0.447, 0.537, 0.532, respectively; P 〈 0.001 for all）.Conclusion There are significant differences as well as associations in thyroid functional indicators （TSH, FT4, TT4 and TT3） among the women during 1st and 2nd trimester of pregnancy. The establishment of region-specific gestation-based reference ranges of thyroid hormones will be helpful to screening, diagnosis and treatment of thyroid diseases among pregnant women.