Objective To examine the iodine nutrition status among pregnant women in Yangpu district, so as to provide evidence for prevention of maternal iodine deficiency diseases.

Methods The iodine nutrition data of pregnant women in Yangpu district 2018 — 2023 were derived from the iodine deficiency disease monitoring and management platform of China center for disease control and prevention, and the iodized salt coverage, qualified rate of iodized salt, consumption rate of qualified iodized salt, salt iodine and urinary iodine were used to assess the iodine nutrition status among pregnant women.

Results A total of 850 pregnant women were involved in this study. The iodine supplement rate among pregnant women was 80.35%, and the salt iodine median was 24.20 (0.00, 28.30) mg/kg. The coverage rate of iodized salt was 60.82%, the qualified iodized salt rate was 90.91%, and the consumption rate of qualified iodized salt was 55.29%. The median salt iodine, iodized salt coverage rate, qualified iodized salt rate, and qualified iodized salt consumption rate among pregnant women in various years were statistically significant differences (P < 0.05). Iodized salt coverage rate showed a downward trend and uniodized salt coverage rate showed an upward trend (P < 0.05). The rates of qualified iodized salt consumption were different among various age group pregnant women, and showing a significant downward trend ( \chi _\mathrmtrend^2 = 8.924, P < 0.05). There was no difference in median salt iodine, iodized salt coverage rate, qualified iodized salt rate, and qualified iodized salt consumption rate among various stages of pregnant women (P > 0.05). The M (P₂₅, P₇₅) of urinary iodine concentration was 136.00 (87.70, 216.00) μg/L. The median level of urinary iodine and the distribution of urinary iodine among pregnant women were significantly different in various years (H = 25.406, χ² = 41.851, P < 0.05). There was no difference in the median level and distribution of urinary iodine in various age groups and different stages of pregnancy (P > 0.05). There was no significant correlation between salt iodine content and urine iodine content in pregnant women (P > 0.05).

Conclusion The coverage rate of iodized salt and the consumption rate of qualified iodized salt among pregnant women in Yangpu district is low, and the median urinary iodine level is not appropriate. It is suggested that the prevention and control strategy of salt iodization should be sustained, health education focusing on pregnant women should be improved, so as to guide scientific iodine intake during pregnancy.