Evidence map›Paper›PMID 40579149›Full record

ArticleEuropean journal of endocrinology2025

Thyroid strain in pregnancy: a nationwide study of iodine nutrition and thyroglobulin among Faroese pregnant women.

Herborg Líggjasardóttir Johannesen, Anna Sofía Veyhe, Pál Weihe, Maria Skaalum Petersen, Stine Linding Andersen, Stig Andersen

Abstract read
In one paragraph

Article in European journal of endocrinology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Evolving Concepts in Gestational Iodine Requirements.Healthcare (Basel, Switzerland) · 2026
    Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Herborg Líggjasardóttir JohannesenDepartment of Endocrinology and Medicine, The National Hospital of the Faroe Islands, Torshavn FO 100, Faroe Islands.ORCID 0000-0002-9048-3303
Anna Sofía VeyheCentre of Health Science, Faculty of Health Science, The University of the Faroe Islands, Torshavn FO 100, Faroe Islands.
Pál WeiheCentre of Health Science, Faculty of Health Science, The University of the Faroe Islands, Torshavn FO 100, Faroe Islands.
Maria Skaalum PetersenCentre of Health Science, Faculty of Health Science, The University of the Faroe Islands, Torshavn FO 100, Faroe Islands.ORCID 0000-0001-9404-8440
Stine Linding AndersenDepartment of Clinical Medicine, Aalborg University, Aalborg DK 9000, Denmark.ORCID 0000-0001-6336-1936
Stig AndersenDepartment of Clinical Medicine, Aalborg University, Aalborg DK 9000, Denmark.

Funding

Vulnerability During Infancy to Immunotoxic Contaminant ExposuresR01ES030394 · NIEHS · UNIVERSITY OF SOUTHERN DENMARK · PI GRANDJEAN, PHILIPPE ADAM · 2020 to 2023
$2.0M
Betri StuðulNIEHS NIH HHS R01 ES030394NIEHS NIH HHS R01ES030394North Denmark Region and Aalborg University HospitalThe Research Council at the National Hospital Faroe Islands
6 · The paper itself

Abstract

objectiveAbnormal thyroid function is particularly problematic in pregnant women. Iodine is important to maintain normal thyroid function, and the World Health Organization (WHO) recommends a raised iodine intake in pregnant compared with non-pregnant adults. The raised iodine intake level from 100 to 150 µg/L includes a safety margin, and we hypothesized that the thyroid is not strained until urinary iodine concentration (UIC) is below 100 μg/L.

designNationwide cross-sectional study.

settingRoutine prenatal care at the National Hospital System of the Faroe Islands, 2020-2022.

participantsA total of 623 pregnant women, representing 63% of all pregnancies in the Faroe Islands during the study period, with no known thyroid disease. EXPOSURE: Iodine-containining dietary intake was assessed indirectly through urinary iodine concentration (UIC) measured on spot urine using the Sandell-Kolthoff reaction. MAIN OUTCOME: The primary outcomes were serum Thyroglobulin (s-Tg) and thyrotropin (TSH) concentration serving as indicators of potential thyroid strain and thyroid function. MEASURES: UIC and TSH was measured in all participants. sS-Tg was measured in a randomly selected subset of 236 participants.

resultsWomen were seen in median gestational week 20. None had elevated TSH; the median UIC was 108 µg/L, and the median s-Tg was 10.3 µg/L. Serum Tg differed only for the group with UIC below 50 µg/L (P = .02), but not when UIC was above 50 µg/L. TSH increased with higher UIC (P < .001). CONCLUSIONS AND RELEVANCE: Thyroglobulin levels increased only in the group of Faroese pregnant women with UIC below 50 µg/L, indicating that strain on the thyroid gland was seen with low UIC levels parallel to that of non-pregnant adults. Our results suggest that the UIC limit recommended in pregnancy may be overly strict and warrant reconsideration to balance health efficacy.

Indexed as

IodineNutritional StatusPregnancy ComplicationsThyroglobulinThyroid GlandAdultCross-Sectional StudiesDenmarkFemaleHumansPregnancyThyroid Function TestsThyrotropinYoung AdultIodineThyroglobulinThyrotropinartic societyawarenessFaroe Islandshealth surveyiodinepregnancythyroglobulinurinary iodine excretion

Identifiers

PMID40579149
PMCPMC12230741

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.