碘适量地区城市妊娠妇女亚临床甲状腺功能异常的研究

Study on subclinical abnormalities of thyroid function in pregnant women in iodine sufficient areas

目的研究碘适量地区城市妊娠妇女亚临床甲状腺功能异常状况,为今后实施妊娠妇女甲状腺功能筛查提供依据。方法随机采集杭州市5个调查点160名妊娠妇女及51名正常非妊娠妇女的血、尿样品,酸消化砷-铈接触法测定尿碘,化学发光法测定促甲状腺激素(TSH)、游离甲状腺素(FT4)、游离三碘甲状腺原氨酸(FT3)、总甲状腺素(TT4)、总三碘甲状腺原氨酸(TT3)和甲状腺过氧化物酶抗体(TPOAb)。结果妊娠早、中、晚期妇女与非妊娠妇女间尿碘水平差异均无统计学意义(Z=2.21,P=0.53);采用正常妊娠妇女甲状腺激素参考值范围检出亚临床甲状腺功能异常率为10.0%(16/160),如采用非妊娠妇女甲状腺激素正常参考值范围,妊娠妇女亚临床甲状腺功能异常漏诊率为8.75%(14/160),两种参考范围在判断亚临床甲状腺功能方面差异有统计学意义(χ2=8.46,P=0.04)。结论必须用正常妊娠妇女不同孕期甲状腺激素参考值范围对妊娠妇女甲状腺功能进行判断。虽然杭州市城市妊娠妇女人群尿碘处于适宜水平,但亚临床甲状腺功能异常检出率为10.0%,建议在早、中期妊娠妇女中开展甲状腺功能筛查。

Objective To study subclinical abnormalities of thyroid function during different trimesters of pregnancy in iodine sufficient areas and provide evidence for monitoring iodine nutrition or screening for thyroid function. Methods The urinary iodine levels and thyroid function were investigated for 160 pregnancy and 51 non-pregnancy subjects of 5 hospitals in Hangzhou. The urinary iodine concentration was measured by arsenic-cerium contact processing method. The serum TSH,FT4,TT4,FT3,TT3 and TPOAb were measured by chemiluminescence method. Results The median concentration of urinary iodine in the 1st,2nd and the 3rd trimester of pregnancy was not different from that of non-pregnant women （Z=2.21,P=0.53）. The rate of subclinical abnormalities of thyroid function was 10.0%（16/160）based on trimester-specific reference intervals of thyroid hormones for normal pregnancy.The rate of missed diagnosis of subclinical hypothyroidism would be 8.75%（14/160）according to the population-based reference intervals. There was significant difference in detecting subclinical hypothyroidism with the two reference intervals（χ2=8.46,P=0.04）. Conclusion We should evaluate thyroid function in pregnant women with trimester-specific reference intervals of thyroid hormones for normal pregnancy.More than half of the pregnant women in Hangzhou had good nutritional status of iodine,while 10.0% of them had maternal subclinical thyroid abnormalities.The thyroid function screening is recommended for pregnant women,especially in the 1st and 2nd trimester.