Isolated Hypothyroxinemia in Iranian Pregnant Women, the Role of Iodine Deficiency: A Population-Based Cross-Sectional Study

Citations Over TimeTop 12% of 2019 papers

Abstract

Background: Thyroid disorders such as subclinical hypothyroidism and isolated maternal hypothyroxinemia are understudied in pregnant women, despite their possible adverse effects on the health of mother and child. Also, the role of iodine deficiency in developing such disorders has not yet been fully understood. Methods: The present national population-based cross-sectional study was conducted on 1080 randomly recruited pregnant women, aged 20-40 from 12 provinces of Iran from 2013 to 2014. Serum concentrations of thyrotropin, T4, thyroid peroxidase antibody (TPOAb), and triiodothyronine (T3) resin uptake values were measured in fasting blood samples, and urinary iodine concentration (UIC) was measured in three separate urine samples. Multinomial logistic regression was run to analyze the possible risk factors regarding thyroid disorders. To clarify the role of iodine in thyroid status specifically, the determinants of UIC and its correlations with thyroid function tests were investigated independently and through subgroup analysis. Results: Isolated hypothyroxinemia was the most common thyroid disorder (9.9%), followed by subclinical hypothyroidism (8%). In comparison to euthyroid pregnant women, isolated hypothyroxinemia was more likely in pregnant women older than 30 years (odds ratio [OR] = 1.6), in the second and the third trimesters (OR = 2.62 and 2.12 respectively), with history of multiparity (OR = 1.72), residing in rural areas (OR = 1.57) and in the capital province of the country (OR = 3.3). Subclinical hypothyroidism was more likely in TPOAb positive pregnant women (OR = 2.56). All the mentioned ORs were statistically significant (p p Conclusion: Isolated maternal hypothyroxinemia was the most prevalent thyroid disorder in Iranian pregnant women and its associated risk factors were identified. Although the calculated prevalence of thyroid disorders was expected in a moderately iodine deficient setting, no correlations between UICs and thyroid function tests were found at the individual level. The contribution of iodine deficiency to thyroid condition for each pregnant woman may be more evident in pregnant women with certain thyroid disorders or those with long-term iodine deficiency.

Related Papers

• → Prevalence of thyroid peroxidase antibody and pregnancy outcome in euthyroid autoimmune positive pregnant women from a tertiary care center in Haryana(2017)48 cited
• → The Effect of Anti-Thyroid Peroxidase Antibodies on Pregnancy Outcomes in Euthyroid Women(2016)39 cited
• → Stability of thyroid function in older adults: the Birmingham Elderly Thyroid Study(2018)28 cited
• → Thyroid peroxidase autoantibody fingerprints in hypothyroid and euthyroid individuals. I. Cross-sectional study in elderly women.(1995)36 cited
• [Correlation of thyroid-stimulating hormone with metabolic syndrome in euthyroid male elders].(2014)