Pregnant Women Are Iodine Deficient While School-Aged Children Demonstrate Adequate Iodine Status in Sarawak, Malaysia

Background: A mandatory universal salt iodization (USI) has been implemented in Sarawak, Malaysia since 2008. Objectives: The aim of this study is to assess the current iodine status among school-aged children (SAC) and pregnant women (PW) after 10 years of USI implementation in Sarawak. Methods: This cross-sectional survey among school-aged children and pregnant women was conducted between July and October 2018 in Sarawak. The multistage proportionate to population size sampling technique was used to select 30 schools and 30 maternal and child health care clinics. A total of 1200 children aged 8 to 10 years and 750 first-trimester pregnant women were randomly selected to participate in the study. Iodine excretion level in urine was determined according to the World Health Organization classification. Results: A total of 988 children and 677 PW participated in the study with a response rate of 82.3% and 90.2%, respectively. The overall median urinary iodine concentration (UIC) level among the children was 126.0 μg/L (interquartile range [IQR], 71.0-200.9 μg/L) and classified as adequate iodine status. The median UIC among PW was 123.9 μg/L (IQR, 56.5-192.1μg/L) indicating inadequate iodine status. Conclusion: The present findings indicate that despite adequate iodine status in children, the majority of PW still showed inadequate iodine status. Thus, comprehensive monitoring of the iodine deficiency disorder problem among PW is warranted.