Urine Iodine Concentration Trends During Pregnancy in The North-Central Region of Nigeria

Main Article Content

Terry Gbaa
John Bolodeoku
Victor Uwe
Arome Okeme

Keywords

Urine iodine concentration, pregnancy, thyroid function test, Thyroid status, Thyroid-stimulating hormone, free thyroxine

Abstract

Background: Pregnancy is a hyperdynamic state that significantly strains the mother's iodine stores due to the demands of the foetus. Iodine deficiency poses significant risks during pregnancy, affecting maternal and foetal health. Thyroid hormones, which are vital for brain development, rely on iodine, and deficiencies can lead to conditions like hypothyroidism and goitre. Monitoring urinary iodine concentration (UIC) is crucial for assessing iodine status, especially in pregnancy, where iodine plays a pivotal role in neurodevelopment. The aim of this study is to determine the urine iodine concentration changes and its adequacy in pregnancy.


Methodology: This descriptive cross-sectional study was conducted over a period of nine (9) months (June 2019–February 2020). The study comprised a cohort of 250 pregnant women who were attending their antenatal clinic visits. These participants were selected randomly using a table of random numbers.  Spot Urine samples were analysed using the Sandell-Kolthoff technique to measure UIC. The data were analysed using Statistical Package for Social Sciences (SPSS) version 21 (IBM, Chicago, IL, USA).


Results: The mean ± SD urine iodine concentration in the 1st, 2nd , 3rd  was (192.02 ± 40.71 µg/L; 185.49 ± 32.94 µg/L I;186.54 ± 35.35 µg/L; p=0.135) respectively Urine iodine Concentration across the 3 trimesters <150 µg/L(<0.01); 150-250 µg/L(<0.01); >250 µg/L(<0.01). The participants’ chronological ages ranged from 17 to 44 years. The mean ± SD, 1st, 2nd , 3rd (26.40 ± 4.70; 27.00 ± 5.10; 28.20 ± 5.20; p=0.211) years respectively.  The Pearson (-0.439; p <0.05) of urine iodine concentration and thyroglobulin.


Conclusion: This study highlights the continued need for public health initiatives that promote iodine awareness and the use of iodized salt among women of reproductive age. Furthermore, the inclusion of thyroglobulin measurement alongside urinary iodine concentration may provide a more comprehensive assessment of thyroid function during pregnancy.

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