Tehran University of Medical Sciences Journal of Family and Reproductive Health 1735-8949 20 1 2026 07 22 71 77 Tiba Mirzarahimi Department of Obstetrics and Gynecology, Alavi Hospital, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran Elham Mikaeili Aghah Department of Obstetrics and Gynecology, Alavi Hospital, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran Shervin Tabrizian Department of Obstetrics and Gynecology, Alavi Hospital, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran Aziz Kamran Department of Community Medicine, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran 2026 02 21 2026 06 09 Objective: This study investigated the association between Anti-TPO levels and ovarian reserve markers, including anti-Müllerian hormone (AMH) and antral follicle count (AFC), in euthyroid infertile women. Materials and methods: In this cross-sectional analytical study, 231 euthyroid infertile women were enrolled and classified as Anti-TPO positive (n = 92) or Anti-TPO negative (n = 139). Serum levels of AMH, FSH, LH, TSH, prolactin, and Anti-TPO were measured, and AFC was assessed by transvaginal ultrasonography. Because hormonal variables were not normally distributed, logarithmic transformation was applied prior to parametric analyses. Data were analyzed using independent t-tests, Pearson correlation, and multivariate regression (α = 0.05). Results: No significant differences were observed between groups in log-transformed AMH, AFC, FSH, or LH levels (p > 0.05). Age was negatively associated with log-AMH. Subgroup analyses demonstrated that in Anti-TPO–positive women, higher Anti-TPO levels were associated with lower log-AMH and higher log-FSH. Multivariate regression identified age as the only independent predictor of log-AMH levels (β = –0.337, p < 0.001). Conclusion: Ovarian reserve decline appears primarily age-related; however, thyroid autoimmunity may have a potential modulatory role in ovarian function. Consideration of thyroid autoantibody status may be clinically relevant in infertility evaluation. https://jfrh.tums.ac.ir/index.php/jfrh/article/view/3675 https://jfrh.tums.ac.ir/index.php/jfrh/article/download/3675/755