Evidence map›Paper›PMID 42036333›Full record

ArticleEndocrine journal2026

Association of hypothyroidism with adverse pregnancy outcomes: a single-center cohort study in an iodine-sufficient country.

Akiko Sankoda, Nagayoshi Umehara, Yusuke Okubo, Shiori Sato, Seiji Wada, Naoko Arata

Abstract read
In one paragraph

Article in Endocrine journal, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing 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

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.

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

0 citing papers in PubMed.

No citing paper in PubMed yet.

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.

Akiko SankodaPreconception Care Center, Integrated Center for Women's Health, National Center for Child Health and Development, Tokyo, Japan.ORCID http://orcid.org/0000-0002-2578-066X
Nagayoshi UmeharaCenter for Maternal-Fetal, Neonatal and Reproductive Medicine, National Center for Child Health and Development, Tokyo, Japan.
Yusuke OkuboDivision of Clinical Epidemiology and Health Services Research, Department of Social Medicine, National Center for Child Health and Development, Tokyo, Japan.
Shiori SatoWomen's Internal Medicine, Women's Health Center, National Center for Child Health and Development, Tokyo, Japan.ORCID http://orcid.org/0009-0005-5053-6641
Seiji WadaCenter for Maternal-Fetal, Neonatal and Reproductive Medicine, National Center for Child Health and Development, Tokyo, Japan.
Naoko ArataPreconception Care Center, Integrated Center for Women's Health, National Center for Child Health and Development, Tokyo, Japan.ORCID http://orcid.org/0000-0003-2667-7653

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Hypothyroidism is reported to associate with adverse pregnancy outcomes. However, there are few reports in iodine-sufficient or -excess areas. We investigated the association of hypothyroidism in early pregnancy with pregnancy outcomes in an iodine-rich area, Japan. We conducted a retrospective cohort study at a tertiary center between 2004 to 2013. The eligible participants were classified into three groups: euthyroidism, subclinical hypothyroidism (SCH), or overt hypothyroidism (OH) groups, based on their thyroid hormone levels in the first trimester of pregnancy (median 11.6 weeks, IQR 10.6-12.6). SCH and OH were defined as elevated TSH levels with normal and low FT4 levels, respectively, using cohort-specific reference ranges in early pregnancy. The primary outcomes were miscarriage, preterm birth, small for gestational age (SGA), and their composite. Multivariate logistic regression analyses and restricted cubic spline analyses fitted to the regression models were performed to analyze the association and dose-dependency. 5,366 pregnant women were classified as euthyroidism, 143 as SCH, and 21 as OH. The composite outcome was not associated with SCH (odds ratio [OR], 0.73; 95%CI, 0.41-1.31), but significantly associated with OH (OR, 3.43; 95%CI, 1.36-8.68). Preterm birth was not associated with SCH (OR, 0.69; 95%CI, 0.28-1.69), but significantly associated with OH (OR, 5.56; 95%CI, 1.98-15.63). In this Japanese single-center cohort, SCH diagnosed in the first trimester was not associated with selected adverse pregnancy outcomes; however, miscarriage risk in early pregnancy could not be adequately assessed. The restricted cubic spline models for the primary outcomes showed J-shaped association with TSH, while the dose-response analysis did not show a clear increase in risk within the reference range of FT4. SCH in early pregnancy was indicated to have no association with the adverse pregnancy outcomes in an iodine-rich area. The risk of adverse pregnancy outcomes was increased exclusively in the low FT4 range.

Indexed as

Abortion, SpontaneousHypothyroidismIodinePregnancy ComplicationsPregnancy OutcomePremature BirthAdultCohort StudiesFemaleHumansInfant, NewbornInfant, Small for Gestational AgeJapanPregnancyPregnancy Trimester, FirstRetrospective StudiesIodineHypothyroidismMiscarriagePregnancyPreterm birthThyroid

Identifiers

PMID42036333
PMCPMC13378838

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

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.