|LETTER TO THE EDITOR
|Year : 2019 | Volume
| Issue : 4 | Page : 983
Maternal thyroid status and its relation to ferritin and vitamin B12 in Saudi pregnant women
Mahmood D. Al-Mendalawi
Department of Paediatrics, Al-Kindy College of Medicine, University of Baghdad, Baghdad, Iraq
|Date of Submission||17-Jul-2019|
|Date of Acceptance||14-Jan-2020|
|Date of Web Publication||18-Aug-2020|
Mahmood D. Al-Mendalawi
P.O. Box 55302, Baghdad Post Office, Postal code 1111, Baghdad
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Al-Mendalawi MD. Maternal thyroid status and its relation to ferritin and vitamin B12 in Saudi pregnant women. Egypt J Intern Med 2019;31:983
|How to cite this URL:|
Al-Mendalawi MD. Maternal thyroid status and its relation to ferritin and vitamin B12 in Saudi pregnant women. Egypt J Intern Med [serial online] 2019 [cited 2020 Sep 27];31:983. Available from: http://www.esim.eg.net/text.asp?2019/31/4/983/292186
I read with interest the distinguished study by Mogahed et al.  published in April–June 2019 issue of the Egyptian Journal of Internal Medicine. The authors studied thyroid status in Saudi pregnant women and its relation to serum ferritin and vitamin B12. They found that serum thyroid-stimulating hormone level was lower in pregnant than nonpregnant women. The most common thyroid disorder was subclinical hypothyroidism (35.5%) followed by overt hypothyroidism (10%) and hypothyroxinemia (2.2%) in pregnant women. Blood hemoglobin (HB) and serum vitamin B12 levels were significantly lower in first and second trimesters of pregnancy compared with controls (P=0.001). Serum free thyroxin was positively correlated with blood HB and serum ferritin, whereas serum thyroid-stimulating hormone was negatively correlated with blood HB and serum ferritin . I assume that these results must be interpreted with caution owing to the presence of the following methodological limitation. It is obvious that precise interpretation of thyroid hormones during pregnancy in a given population necessitates using local trimester-specific reference intervals. Truly, trimester-specific reference ranges for thyroid hormones have been constructed for certain populations ,. In the study methodology, Mogahed et al.  mentioned that they referred to two standards in assessing thyroid status in their studied population, namely the guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and the currently available report that included normal pregnant participants from the Gulf region. I assume that both standards cannot be applied to the Saudi pregnant population. The first standard was designed for white population , whereas the second standard was constructed for mixed ethnic pregnant population in the United Arab Emirates . Kingdome of Saudi Arabia is not a multi-ethnic country. I assume that formulation of trimester-specific normative data of thyroid hormones for Saudi pregnant women is of utmost importance. Employment of that national standard in the clinical settings and researches could better define the prevalence of thyroid disorders and associated factors in Saudi pregnant women.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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