ArticleThe Journal of nutrition2021
Iodine Nutrition and Iodine Supplement Initiation in Association with Thyroid Function in Mildly-to-Moderately Iodine-Deficient Pregnant and Postpartum Women.
Article in The Journal of nutrition, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 2 registered trials, which are not on this map. Cited by 16 papers, 2 of them syntheses that pooled it.
What it found
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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.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Iodine Status During Pregnancy and Its Effect on Infant Development; a Randomized Intervention Study With Cod
Study on the Displacement of Iodine Balance Value During Pregnancy and the Mechanism of Breast Iodine Homeostasis During Lactation Under Different Iodine Exposure
Who cites it
16 citing papers in PubMed, 2 syntheses or guidelines pooled it, 22 citations in OpenAlex.
- Effects of different iodine supplementation strategies on thyroid function in iodine-deficient pregnant women: a meta-analysis.Frontiers in public health · 2026Pooled it
- Do Postpartum Maternal Iodine Status or Supplementation Affect Thyroid Function After Delivery? A Systematic Review and Meta-Analysis.Biological trace element research · 2024Pooled it
- The effectiveness of education-based interventions on iodine knowledge, attitude, behaviour, and status: a systematic review protocol.Systematic reviews · 2026Article
- Impact of habitual seaweed consumption on iodine nutrition and thyroid function: a non-randomized pre-post clinical study.European journal of nutrition · 2026Article
- Inadequate iodine status among women of childbearing age in Northern Norway: a cross-sectional study.Food & nutrition research · 2025Article
- Micro-nutrient sufficiency in mothers and babies: management of deficiencies while avoiding overload during pregnancy.Frontiers in nutrition · 2025Review
- Urinary iodine concentration and thyroid function in pregnant women with hypertensive disorders.Frontiers in endocrinology · 2025Article
- Iodine intake in the Swiss population 100 years after the introduction of iodised salt: a cross-sectional national study in children and pregnant women.European journal of nutrition · 2024Article
- Iodine Nutrition in Children ≤2 years of Age in Norway.The Journal of nutrition · 2023Article
- Effect of Iodine Nutrition Status on Thyroid Function and Pregnancy Outcomes.Biological trace element research · 2023Article
- Midwives and public health nurses' knowledge and clinical practice in securing sufficient iodine status in relation to pregnancy: A cross-sectional study.Nursing open · 2023Article
- Infant iodine status and associations with maternal iodine nutrition, breast-feeding status and thyroid function.The British journal of nutrition · 2023Article
- A Scoping Review of Iodine and Fluoride in Pregnancy in Relation to Maternal Thyroid Function and Offspring Neurodevelopment.Advances in nutrition (Bethesda, Md.) · 2023Article
- Review
- Antenatal thyroid hormone therapy and antithyroid drug use in Norway from 2004 to 2018.Endocrine connections · 2022Article
- Life-course perspectives of milk consumption among young Norwegian women and their knowledge of milk as a source of iodine: a qualitative study.Food & nutrition research · 2021Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundWhereas the adverse effects of severe iodine deficiency during pregnancy are well documented, the effects of mild-to-moderate deficiency are not well established.
objectivesWe aimed to explore whether iodine nutrition and timing of iodine supplement initiation are associated with thyroid function in pregnant and postpartum women.
methodsIn this cohort study, 137 pregnant women were enrolled and followed up at gestational weeks (GWs) 18 and 36, and 3 and 6 mo postpartum. Thyroid function tests [thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4)], urinary iodine and creatinine concentration (UIC:Cr), and iodine intake (including iodine supplement use) were measured at each time point. The associations between thyroid hormone concentrations and UIC:Cr, iodine intakes, and iodine supplement use were estimated using multiple generalized estimating equation models.
resultsThe median UIC at GW18 was 94 μg/L, indicating mild-to-moderate iodine deficiency. UIC:Cr (β; 95% CI) per 100 μg/g was negatively associated with fT3 (-0.191; -0.331, -0.051) and fT4 (-0.756; -1.372, -0.141) concentrations. Iodine intake (β; 95% CI) per 100 μg/d was positively associated with TSH (0.099; 0.022, 0.177), and negatively associated with fT3 (-0.084; -0.0141, -0.027) and fT4 (-0.390; -0.599, -0.182) concentrations. Compared with no use of supplement, those initiating an iodine-containing supplement prepregnancy and continuing through pregnancy had lower TSH (estimated means) (1.35 compared with 1.68 mIU/L, P = 0.021), and higher fT3 (4.48 compared with 4.28 pmol/L, P = 0.035) and fT4 (15.2 compared with 14.4 pmol/L, P = 0.024) concentrations.
conclusionsLower iodine availability during pregnancy and postpartum was associated with lower TSH, and higher fT3 and fT4 concentrations. The use of an iodine-containing supplement that was initiated prepregnancy and continuing through pregnancy was associated with lower TSH, and higher fT3 and fT4 concentrations, which may suggest improved thyroid function. These findings support the notion that optimization of iodine intake should start before pregnancy.This trial was registered at clinicaltrials.gov as NCT02610959.
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Registered trials
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.