Endometriosis is a common condition among women and can cause complications such as abdominal pain, dysmenorrhea, and infertility. One of the potential causes of this disease is autoimmunity. However, evidence regarding the role of autoimmunity is conflicting and inconclusive. The aim of this study was to investigate whether autoantibodies, a sign of autoimmunity, are present in people suffering from endometriosis. Relevant studies up to April 14, 2023 were identified by systematically searching Scopus, PubMed, Web of Science, Embase, and Google Scholar. This meta -analysis includes all qualified case -control studies of human populations that analyzed the association between serum autoantibodies and endometriosis. The odd ratios and 95% confidence intervals were calculated. In addition, heterogeneity and publication bias were examined, and subgroup analyses were performed based on region and target antigens. Forty-one studies were included, comparing 2,825 endometriosis patients with 4,158 healthy controls. The meta -analysis findings indicated a significant association between the presence of autoantibodies in the serum and an increased susceptibility to endometriosis (odds ratio: 4.242, confidence interval 95%: 3.824-4.706, p<0.001). In addition, there was a significant correlation between the presence of endometriosis and serum levels of anti-nuclear antibodies, B2 glycoprotein 1, CA125, carbonic anhydrase 1, cardiolipin, endometrial, laminin-1, smooth muscle, and syntaxin autoantibodies. Upon further analysis, it was found that the serum levels of these autoantibodies were higher in patients with endometriosis from North America than in those from other regions (p=0.001). The study revealed a significant correlation between serum autoantibodies and susceptibility to endometriosis, highlighting autoimmunity as a potential cause.
