P-684 Subclinical hypothyroidism and ovarian reserve indices in women with normogonadotropic anovulation

Abstract Study question Does subclinical hypothyroidism (SCH) affect ovarian reserve indices in women with Polycystic Ovary syndrome (PCOS) or other forms of Hypothalamic-Pituitary-Ovarian Axis Dysfunction (HPOD)? Summary answer SCH increases Anti-Müllerian hormone (AMH) concentration, but has no influence on Follicle-stimulating (FSH). What is known already In PCOS, anovulation caused by the arrest growing follicles due to increased frequency and amplitude luteinizing (LH) pulses, resulting number pre-antral antral follicles, concentration AMH. cases HPOD, causes are more diverse have not yet been clearly identified. Thyroid hormones can modify function HPO axis, affecting maturation follicles. While overt treated improve ovulation fertility, effect presence circulating antithyroid antibodies (ATA) uncertain. design, size, duration A prospective cohort tertiary single-center study (consent no. 1072.6120.172.2022) included aged 18-45, examined menstrual disorders and/or infertility, from July August 2022. Only without previously diagnosed thyroid dysfunction were included. All enrolled gave informed written consent participate study. Participants/materials, setting, methods Women underwent routine gynecological examination pelvic ultrasound. Blood sample was tested for AMH, FSH, Luteinizing (LH), Thyroid-stimulating (TSH), anti-thyroid peroxidase (anti-TPO) anti-thyroglobulin (anti-TG) concentrations. The Rotterdam-ESHRE-ASRM criteria used diagnose PCOS its phenotypes. HPOD according WHO classification. defined as TSH > 2.5 uIU/ml normal function. above parameters within subpopulations calculated using regression analysis, Kruskal-Wallis post-hoc tests. Main results role chance 51 euthyroid 18-40. 42/51 (82.35%) women, including PCOS-A phenotype 31/51 (60.78%), PCOS-B 5/51 (9.8%), PCOS-D 6/51 (11.76%) 9/51 (17.65%) women. There a significant positive correlation between AMH studied population - increase value, (r = 0.4, p 0.0035). mean significantly differed groups equaled 55.4, 39.4, 31.1, 24.0 pmol/l PCOS-A, PCOS-B, (p 0.05), respectively. anti-TPO different equal 18.2, 19.0, 14.6, 10.9 U/ml difference LH, TSH, anti-TG concentrations groups. Limitations, reasons caution limitations small group nature. Wider implications findings which may exacerbate symptoms anovulation. Whether treatment affects improves remain subject further research. Trial registration 1072.6120.172.2022