[Iodine nutritional status of the vulnerable population in Henan province in 2011].

Objective: To investigate the iodine nutritional status of the vulnerable population in Henan in 2011.
Methods: From March to December 2011, 44 049 urinary samples of newly married women of childbearing age (363), pregnant women (31 874), lactating women (4893) and children under 2 years (6919) collected from hospitals, maternal and child care hospitals and outpatient department of family planning organizations from 8 cities of Henan province (only including the areas where water iodine was less than 100 µg/L) were tested for urine iodine concentration. The iodine nutritional status of different groups was analyzed.
Results: The median of urinary iodine for newly married women, pregnant women, lactating women and children under 2 years was 204.5, 190.9, 145.5 and 185.4 µg/L, respectively (χ(2) = 874.16, P < 0.01). The proportion of urinary iodine below 150 µg/L of pregnant women and below 100 µg/L of lactating women and children under 2 years was 33.0% (10 519/31 874), 24.9% (1218/4893) and 12.4% (855/6919), respectively. The proportion of urinary iodine above 300 µg/L of newly married women was 33.6% (122/363). The median of urinary iodine for pregnant women in the first, second and third trimester was 186.7, 193.8 and 182.5 µg/L, respectively (χ(2) = 55.19, P < 0.01). The median of urinary iodine for the breast-feeding, formula-feeding and mixed-feeding infant under the age of 1 year was 194.8, 85.6 and 176.0 µg/L, respectively (χ(2) = 179.25, P < 0.01).
Conclusion: The overall iodine nutrient levels of the vulnerable population in Henan in 2011 were appropriate, but there were still some proportions of pregnant and lactating women with low iodine level. The iodine intake of the formula-feeding infants was not sufficient.