南京地区中晚期妊娠妇女甲状腺激素参考值范围的初步调查及甲状腺功能分析

An initial investigation of the serum thyroid hormone reference ranges and analysis of the maternal thyroid function during pregnancy in the 2nd and 3rd trimester in Nanjing area of China

目的建立南京地区碘适量的中晚期妊娠妇女甲状腺激素的正常参考范围,并以此为依据来评价妊娠期间母体的甲状腺功能。方法经过严格筛选得到505例碘适量的妊娠14～40周妇女和160例非妊娠期健康妇女,检测血清促甲状腺激素(TSH)、游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、甲状腺过氧化物酶抗体(TPOAb)以及尿碘水平,建立甲状腺激素参考值范围,分析孕妇甲状腺功能。结果与健康非妊娠对照组比较,妊娠中、晚期孕妇血清TSH水平显著增高,以妊娠晚期最为明显,差异均有统计学意义(P<0.05);妊娠中、晚期孕妇的血清FT3和FT4水平显著下降,以妊娠晚期最为明显,差异均有统计学意义(P<0.05)。妊娠中、晚期妇女TPOAb的水平高于非妊娠健康妇女,差异有统计学意义(P<0.05)。结论妊娠妇女的甲状腺激素水平不同于非妊娠健康妇女,中、晚孕期之间差异也有统计学意义。因此,建立妊娠月份特异性的血清甲状腺激素参考值范围对于诊断妊娠亚临床甲状腺功能减退症和低FT4血症是必要的。

Objective To establish the trimesters-specific reference ranges of thyroid hormones for healthy pregnant women in 2 nd and 3 rd trimester with sufficient iodine in Nanjing area of China and to provide evidence to evaluate the maternal thyroid function during pregnancy.Methods 160 non-pregnant healthy women（as the control group）and 505 pregnant women at gestational ages from 14 to 40 weeks with sufficient iodine were collected according to the strict criteria.The levels of serum thyroid stimulating hormone（TSH）,free triiodothyronine（FT3）,free thyroxine（FT4）,thyroid peroxidase antibody（TPOAb）and urinary iodine were measured.The reference range of thyroid hormone was established and the thyroid function of pregnant women was analyzed.Results Compared with healthy non-pregnant women,serum TSH levels elevated markedly in 2 nd and 3 rd trimaster,especially in the 3 rd trimaster,and the differences were statistically significant（P0.05）.Serum FT3 and FT4 levels gradually decreased in 2 nd and 3 rd trimaster,especially in the 3 rd trimaster,and the differences were statistically significant（P0.05）.The level of TPOAb in pregnant women was higher than that of non-pregnant women,and the difference was statistically significant（P0.05）.Conclusion The thyroid hormone levels during pregnancy differ completely from those of the non-pregnant individuals,and also differ during different gestation periods.Therefore,the gestational month-pecific reference intervals of thyroid hormones are necessary for diagnosis of subclinical hypothyroidism and low FT4 syndrome in pregnancy.