Iodine supply of pregnant women in the Czech Republic

Czech version

Authors: Radovan Bílek ¹; Nataša Kaňová ¹; Veronika Mindžáková ²; David Neumann ³; Jan Jiskra ⁴; Lydie Ryšavá ⁵; Václav Zamrazil ¹
Authors‘ workplace: Endokrinologický ústav, Praha ¹; Gynekologicko-porodnické oddělené Oblastní nemocnice Mladá Boleslav, a. s. ²; Dětská klinika LF UK a FN Hradec Králové ³; III. interní klinika 1. LF UK a VFN v Praze ⁴; Meziresortní komise pro řešení jodového deficitu při Státním zdravotním ústavu, Praha ⁵
Published in: Vnitř Lék 2016; 62(Suppl 3): 10-16
Category: Original Contributions

Overview

Introduction:
Iodine deficiency is a global public health problem which is particularly noticeable in pregnant or breastfeeding women and their children. Even mild iodine deficiency during pregnancy can lead to damage to the developing brain and thus affecting the fetus intelligence, his cognitive and neurological function, embryogenesis and growth.

Patients:
In the period 2010–2015 was determined by spectrophotometry at the Institute of Endocrinology the basal urinary iodine in 532 pregnant women at the age of 32 ± 5 (18–44) years, which came from Prague, Hradec Kralove and Mlada Boleslav. It was located 349 women in the first trimester, 112 in the second trimester, and 71 women in the third trimester. In the monitoring of pregnant women in the first trimester 218 basal urine samples of women were determined by mass spectrometry with inductively coupled plasma (ICP MS) in The National Institute of Public Health (NIPH). Women came from the 6 areas in the Czech Republic. Development of urinary iodine in the general population in the period 1994–2015 was observed in patients who underwent Institute of Endocrinology and from population studies conducted in 7 regions of the Czech Republic. It performed 52 648 spectrophotometric analysis of urinary iodine in the general population.

Methods:
Urinary iodine was determined by alkali melting of urine samples, followed by spectrophotometric determination of iodine in the form of iodide using the Sandell-Kolthoff reaction in the Institute of Endocrinology or determination was performed by ICP-MS in the laboratory of NIPH.

Results:
On average, only 21.8 % of pregnant women had urinary iodine values determined by spectrophotometry higher than 150 μg/L. The results of iodine nutrition of pregnant women in the first trimester analyzed using ICP-MS are better, but even so, only 50.5 % of pregnant women have urinary iodine higher than 150 μg/L.

Conclusion:
The results of iodine nutrition of pregnant women are alarming, on average, only 30 % of the total of 750 examined women have urinary iodine values greater than 150 μg/L and therefore meet the requirements of the WHO for pregnant women. Our results, however, show that iodine deficiency is not major public health problem in the general population.

Key words:
ICP-MS – pregnant women – Sandell-Kolthoff reaction – urinary iodine

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