Autoimmune thyroid disease in infertility and assisted reproductive technology: A review.

Autoimmune thyroid disease (ATD), implicated in infertility and unfavorable outcomes in assisted reproductive technology (ART), is the most prevalent autoimmune disorder among women of reproductive age. This review summarizes the existing evidence on the impact of ATD on infertility and ART outcomes, with a particular focus on screening and therapeutic options. Subclinical hypothyroidism (SCH) frequently coexists with ATD. Thyroid-stimulating hormone (TSH) thresholds for SCH treatment in fertility range from 2.5 to 4.0 mIU/L, causing inconsistencies in clinical management. Although levothyroxine is widely recommended for TSH >4.0 mIU/L, benefits for lower thresholds remain controversial. Immunomodulatory therapies, such as glucocorticoids and intravenous immunoglobulin, have uncertain efficacy in improving ART outcomes. This review highlights the pressing need for standardized diagnostic criteria and therapeutic interventions to optimize fertility outcomes in ATD-positive women, particularly with SCH.