Analysis of iodine nutritional status and thyroid function of pregnant and lactating women in urban areas of Wuwei City of Gansu Province

Objective To find out the iodine nutritional status and thyroid function of pregnant and lactating women in the urban areas of wuwei City of Gansu Province, and to provide a scientific basis for iodine supplementation. Methods Blood and urine samples of pregnant （52 persons） and lactating women （59 persons ） were collected in 2009. Urinary iodine content was measured with arsenic cerium catalytic speetrophotometric. Serum free three triiodothyronine （FT3）, free thyroid hormone （FT4）, triiodo thyronine （TT3）, serum total thyroxine （TT4） and thyroid-stimulating hormone （TSH） were detected with direct chemiluminescence immunoassay. Results The medians urinary iodine of pregnant and lactating women were 274.68, 217.88 μg/L. The rates of low urinary iodine （pregnant women below 150 μg/L, lactating women lower than 100 μg/L） were 9.62%（5/52） and 6.78% （4/59）. Serum TT3, TT4 levels in pregnant women[（2.48 ± 0.59）, （132.18 ±33.36）nmol/L] were higher than that in the lactating women[（2.16 ± 0.49 ）, （ 108.79 ± 28.36）nmol/L, t =-3.123, - 3.971, all P 〈 0.05]. Thyroid dysfunction incidence rates of pregnant and lactating women were 17.31% （9/52） and 8.47% （5/59）. Thyroid dysfunction was mostly subclinical hypothyroidism. Conclusions Overall iodine nutrition of pregnant and lactating women is in good condition, some individuals have the trend of hypothyroidism. It is necessary to carry out routine monitoring of urinary iodine and thyroid function. Key words: Pregnancy; Lactating women; Iodine nutrition; Thyroid function