Autoimmune thyroiditis in pregnancy: epidemiology, clinical impact, and contemporary management challenges

Autoimmune thyroiditis represents the most common cause of thyroid dysfunction in women of reproductive age and is frequently encountered during pregnancy. The presence of thyroid autoantibodies, particularly anti-thyroid peroxidase antibodies, has been associated with adverse obstetric outcomes even in the absence of overt thyroid dysfunction. However, optimal screening, monitoring, and treatment strategies remain areas of ongoing debate. This study aimed to review recent evidence on the epidemiology, clinical impact, diagnosis, management, and emerging research directions of autoimmune thyroiditis in pregnancy. A narrative review of observational studies, randomized controlled trials, meta-analyses, and international clinical guidelines published predominantly within the last five years was conducted, focusing on maternal and fetal outcomes, diagnostic approaches, and therapeutic strategies. Autoimmune thyroiditis affects a substantial proportion of pregnant women worldwide and is associated with increased risks of miscarriage, preterm delivery, hypertensive disorders of pregnancy, and postpartum thyroiditis. These associations are observed not only in women with overt or subclinical hypothyroidism but also in euthyroid women with thyroid autoimmunity. While levothyroxine therapy is clearly indicated in overt and selected cases of subclinical hypothyroidism, evidence does not support routine treatment in euthyroid antibody-positive women. Current guidelines recommend targeted screening and close biochemical monitoring rather than universal intervention. Autoimmune thyroiditis in pregnancy is a clinically relevant condition with important implications for maternal and fetal health. A risk-stratified, individualized approach to diagnosis and management is essential, balancing the benefits of treatment against the risks of overtreatment. Further high-quality research is needed to refine risk prediction and identify subgroups that may benefit from targeted therapeutic interventions.