A total of 404 pregnant women during early pregnancy in our hospital were enrolled. The general information of patients was collected；the levels of serum ferritin （SF）， haemoglobin （Hb）， free thyroxine （FT4），thyroid-stimulating hormone（TSH），TPOAb， urinary creatinine （UCr） and urinary iodine concentration（UIC） were measured in the pregnant women.The pregnant women were divided into iodine deficiency group（UIC/UCr<150 μg·g^－1），idodine adequate group（150 μg·g^－1 ≤UIC/UCr<250 μg·g^－1）and more-than-adequate/excessive iodine group（UIC/UCr≥250 μg·g^－1） according to the different idodine levels.The pregnant women were divided into iron deficiency group（SF<20 μg·L^－1），iron adequate group（20 μg·L^－1≤SF<150 μg·L^－1） and iron excess group（SF≥150 μg·L^－1） according the different iron levels.The thyroid function，the serum TPOAb positive rates and the prevalence of subclinical hypothyroidism and subclinical hyperthyroidism of the pregnant women in various groups were compared.

The median of TSH， FT4， UIC/UCr and SF of 404 pregnant women were 1.15 mIU·L^－1 （0.62 mIU·L^－1，1.63 mIU·L^－1）， 12.96 pmol·L^－1（12.06 pmol·L^－1，13.96 pmol·L^－1），158.66 μg·g^－1（106.93 μg·L^－1，239.41 μg·L^－1） and 60.93 mg·L^－1（33.86 μg·L^－1，89.61 μg·L^－1）.The serum TSH levels of pregnant women in iodine deficiency group and more-than-adequate/excessive iodine group were higher than that in iodine adequate group （P<0.05）. The TPOAb positive rate in more-than-adequate/excessive iodine group was higher than those in iodine deficiency group and iodine adequate group （P<0.05）； the FT4 levels had no significant differences among various groups （P>0.05）.The serum TSH levels and the TPOAb positive rate of pregnant women in iron deficiency group were higher than those in iron adequate group and iron excess group （P<0.05）. The FT4 level of pregnant women in iron deficiency group was lower than that in iron excess group （P<0.05）. The prevalence of subclinical hypothyroidism in the pregnant women in iodine deficiency group and more-than-adequate/excessive iodine group was higher than that in iodine adequate group （P<0.05）. However， the prevalence of subclinical hypothyroidism in the pregnant women in iron deficiency group was higher than those in iron adequate group and iron excess group（P<0.05）， and the prevalence of subclinical hyperthyroidism in iron excess group was higher than those in iron deficiency group and iron adequate group（P<0.05）. The further correlation analysis results revealed that the UIU/UCr ratio had no correlations with the TSH and FT4 levels of the pregnant women（P>0.05））；the SF level was negatively correlated with the TSH level （r=－0.148，P<0.05）， and positively correlated with the TSH level （r=－0.150，P<0.05）.

The nutritional levels of iron and iodine of the pregnant women in early pregnancy is related to thyroid function and thyroid autoimmunity， and the nutritional condition of iron and iodine should be assessed promptly， the individualized supplement of iodine and iron should be done， at the same time， the excessive iodine supplement should be avoided.