Metabolic & Cardiometabolic
PCOS worsens thyroid function
Part of: • PCOS
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
What the evidence shows
PCOS is associated with higher thyroid autoimmunity (anti-TPO / Hashimoto) and subclinical hypothyroidism.
The evidence (5)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Bahreiny SS, Ahangarpour A, Amraei M, et al. 2024 · J Reprod Immunol | meta-analysis | supports | moderate | SR+MA, 18 studies / 3657 participants: PCOS-autoimmune-thyroiditis OR 2.38 (1.63-3.49); anti-TPO SMD 0.36 (0.19-0.53); anti-TG SMD 1.24 (0.37-2.10); TSH SMD 0.24 (0.06-0.42). |
| pcos-ht-ovarian-2021 2021 | observational | mixed | low | Case-control: among PCOS, coexisting Hashimoto's worsened ovarian markers — documents elevated HT burden within PCOS. |
| Kwiatkowski S, et al. 2025 · Int J Mol Sci | meta-analysis | mixed | moderate | anti-TPO prevalence OR 2.03 (1.35–3.04); attenuates somewhat in TSH/BMI-matched subgroups. |
| Rasoulizadeh Z et al 2025 · study_type: observational | observational | supports | medium | Case-control, Iran, n=1047 PCOS vs 1047 age-matched controls (Rotterdam). Anti-TPO Ab higher in PCOS (median 12.0 vs 4.0 IU/mL; p=0.002); TSH not sig. different (p=0.073, borderline higher in PCOS). Anti-TPO+ in 12.89% of PCOS. |
| hashimoto-2015 2015 | observational | supports | moderate | Case-control: high Hashimoto prevalence in PCOS vs controls. |
Disagree, or know a study we missed?
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.