Contemporary view and clinical implications of thyroid autoimmunity interactions in female fertility, reproduction and pregnancy

Abstract

Thyroid autoimmunity (TAI) is known to influence female reproductive function and has been identified in 13–19% of infer-tile women, particularly in those with recurrent miscarriage, polycystic ovary syndrome (PCOS), diminished ovarian reserve, reduced embryo quality, or unexplained infertility. This review examines the relationship between TAI, including subclinical and overt hypothyroidism, as well as postpartum thyroiditis (PT), and female reproductive health, emphasizing the role of TAI in female subfertility. This narrative literature review draws on key medical databases to analyze recent and available evi-dence-based studies exploring the influence of TAI on ovarian function, fertility and pregnancy. TAI, even in its asymptomatic or subclinical forms, may impair fertility through direct ovarian mechanisms and immune-mediated pathways. Thyroid anti-bodies are associated with unexplained infertility and idiopathic low ovarian reserve that might be linked to one another. PT pre-sents an additional challenge when pregnancy is followed by thyroid dysfunction, particularly in TPOAb-positive women. TAI should be considered in the diagnostic evaluation of subfertile women, especially those with unexplained subfertility or pregnancy loss/termination. Monitoring and individualized LT-4 therapy may improve reproductive outcomes and reduce pregnancy complications. Further research is needed to clarify the immune mechanisms linking TAI and reproductive failure.