Pregnant Women in Austria Experience Iodine Deficiency

A new study suggests that pregnant women in Austria have a potentially clinically significant iodine deficiency which could impair embryonic brain development.

Researchers at the Medical University of Vienna (Austria) conducted a cross-sectional investigation of urinary iodine excretion in 246 pregnant women (2 in the first trimester, 53 in the second trimester, and 191 in the third trimester) to determine the presence of iodine deficiency during gestation, which can lead to neurocognitive deficits. Of these, 115 women suffered from gestational diabetes mellitus. The urinary iodine concentration (UIC) of morning spot urine samples was determined using inductively coupled plasma mass spectrometry.

The results revealed that only 13.8% of the cohort of pregnant women in the Vienna area were in the recommended UIC range of 150–249 μg/L, with the median being 187 μg/L. A total of 137 women of foreign origin, however, had a significantly higher UIC compared with Austrian-born women. And although 79 women on iodine supplementation had a significantly higher iodine concentration compared with women without supplementation, their UIC was still below the recommended range, indicating that doses of 100–150 μg per day are not sufficient to normalize iodine excretion. The study was published ahead of print on December 10, 2014, in the European Journal of Clinical Nutrition.

“According to the WHO, every pregnant woman should take around 250 micrograms of iodine a day, and this should be continued until she stops breast feeding,” concluded lead author Heidelinde Lindorfer, PhD, and colleagues. “Before, during, and after pregnancy, however, iodine is extremely important for embryonic brain development. Even a mild iodine deficiency can impair the child's intellectual development; recent studies in the UK and Australia have shown that IQs are in fact reduced by a few points.”

“This leads to the conclusion that women need to take higher quantities of iodine if they are planning to become pregnant," concluded Dr. Lindorfer. “Once they are pregnant, it is too late. By this point, iodine stores are clearly so empty that they cannot be adequately topped up during pregnancy due to the approximately 50% higher demand for iodine.”

The Austrian population is already susceptible to a certain deficiency of iodine, since the country retains of the lowest levels of salt iodination in the world, at just 15 to no more than 20 milligrams per kilogram of salt; over the years, this figure has actually fallen. By contrast, the World Health Organization (WHO; Geneva, Switzerland) recommends 20–40 milligrams per kilogram of salt.

Related Links:
Medical University of Vienna
World Health Organization