Objective To analyze the iodine nutritional status in pregnant women and children aged 8 to 10 years in Lanzhou in 2020.

Methods The surveillance data of iodine deficiency disorders were collected from key populations in Lanzhou in 2020, which included iodides in edible salt (salt iodine), iodides in urine (urine iodine), and pediatric thyroid volume indices of pregnant women and children in five districts and three counties in Lanzhou. A statistical analysis was performed on the levels of and differences in these indices in different populations.

Results A total of 2 410 salt samples were collected in 2020. The mean salt iodine level was 26.35±4.65 mg/L, the iodized salt coverage rate was 99.54%, and the qualified iodized salt intake rate was 91.16%. The median urine iodine concentration M (P₂₅, P₇₅) of 1 610 investigated children aged 8 to 10 years was 208.95 (139.45, 285.68) μg/L, among which 298 samples (18.51%) had a urine iodine concentration greater than 300 μg/L. The incidence rate of goiter in children was 0.74%. There were significant differences in thyroid volume among children of different districts/counties, ages, and sexes (χ²=100.10, χ²=92.81, Z=3.19, P<0.05). The M (P₂₅, P₇₅) value of urine iodine of 800 urine samples from pregnant women was 166.75 (105.51, 253.98) μg/L, and the urine iodine concentration was less than 150 μg/L in 320 samples (40.00%). There was no significant difference in the mean urine iodine level in different durations of pregnancy (χ²=0.31, P>0.05). There was no significant difference in the composition of urine iodine levels in different durations of pregnancy (χ²=6.63, P>0.05).

Conclusion In 2020, the iodine nutritional level was generally appropriate in pregnant women and children aged 8 to 10 years in Lanzhou, but iodine excess in children and iodine nutritional deficiency in pregnant women were observed.