The impact of mandatory iodine fortification and supplementation on pregnant and lactating women in Australia.

BACKGROUND AND OBJECTIVES

In Australia, two public health measures were introduced between 2009 and 2010 to reduce iodine deficiency. However there has been a shortage of information regarding their effectiveness and the ongoing prevalence of iodine deficiency in Australia. The primary aim of this study was to assess the extent to which these public health measures have reduced rates of iodine deficiency among pregnant and lactating women.

METHODS AND STUDY DESIGN

A review was conducted to identify all studies published since January 2010 that quantitatively measured the iodine status of pregnant and/or lactating women in Australia.

RESULTS

We found 25 publications, of which seven were included in this review after our exclusion criteria were applied. Of the seven included publications, three demonstrated the pregnant and lactating women in their studies to be iodine replete (median urinary iodine concentrations (MUIC) greater than 150 μg/L, or a breast milk iodine concentration (BMIC) of greater than 100 μg/L). The remaining four publications found MUIC of pregnant and lactating women to be below the 150 μg/L threshold, in the mild-to-moderate iodine deficiency category. Only two studies, documented iodine sufficiency among pregnant and lactating women in the absence of iodine supplementation.

CONCLUSIONS

Many pregnant and lactating women in Australia remain at least mildly iodine deficient. Antenatal iodine supplementation was the factor most consistently associated with an adequate iodine status. Larger, more representative studies or sentinel studies with a National coordination are needed to understand the differences in iodine status that exist across the country.