Antinuclear Antibodies in Polycystic Ovary Syndrome: A Systematic Review of Observational Studies.

Polycystic ovary syndrome (PCOS), the most common endocrine disorder in reproductive-age women, is characterized by menstrual irregularities and polycystic ovarian morphology. It is also associated with insulin resistance, chronic inflammation, and oxidative stress, all of which may promote autoimmunity. Several studies have suggested a higher occurrence of antinuclear antibodies (ANA) in PCOS but the main challenge in this field is the inconsistency of findings due to heterogeneous study designs and assay methods. However, to date, no systematic review has synthesized this evidence. We conducted a systematic review to evaluate the prevalence and serum levels of ANA in women with PCOS. A comprehensive search was performed in PubMed, Embase, and Scopus, and 13 studies were ultimately included, comprising 924 women with PCOS and 1172 controls. ANA were elevated in about half of the studies, while the remainder found no significant differences between PCOS and controls. Anti-dsDNA antibodies were the most consistently investigated ANA subtype, with most studies reporting higher levels or prevalence in PCOS. For other ANA subtypes, the evidence was limited and inconclusive, largely due to methodological variability across studies. This systematic review suggests that ANA may be elevated in a subset of women with PCOS, but the current evidence remains inconsistent. These findings highlight the need for methodological standardization in ANA assessment to enable clearer conclusions and to clarify whether ANA positivity has clinical relevance in this population.