Is an Established Urinary Iodine Criterion for Population Valid to Assess Adequacy of Iodine Status during Pregnancy?

Abstract

To control iodine deficiency disorders (IDD), measurement the size and severity of IDD problem in vulnerable groups is a vital step. World Health Organization has established urinary iodine at a level of less than 100 microgram per liter as a criteria indicating iodine deficiency. And school children, a vulnerable group, are recommended as a target group for monitoring the IDD problem in a community. Unfortunately, there are evidences suggesting that there is iodine inadequacy among pregnant women in areas where median urinary iodine in school children indicate adequate iodine status. In addition, there are communities of which pregnant women have higher urinary iodine than non-pregnant women in the same community. Thus, monitoring IDD problem only among school children is not sufficient and the established criterion for population might be too low in indicating IDD among pregnant women. And, applying established criteria to this vulnerable group will lead to underestimated IDD problem. Therefore, the scientists proposed the cutoff for this particular group that it should be increased to 120-150 microgram per liter. However, presently there are limited data to establish the appropriate urinary iodine criterion for pregnant women.