Maternal autoimmune diseases and the risk of autism spectrum disorders in offspring: A systematic review and meta-analysis

•A systematic review and meta-analysis based on nine case-control studies and one cohort study.•Association between maternal autoimmune diseases and the risk of autism spectrum disorders in offspring.•Maternal autoimmune diseases increasing the risk of autism spectrum disorders in offspring. Although inherited and immune disorder factors are known to be involved in autism spectrum disorders (ASD), controversy still exists as to whether maternal autoimmune disease is an independent risk of ASD in offspring. We aimed to quantitatively summarize the risk of ASD in offspring in relation to maternal autoimmune diseases. A literature search in Pubmed, Web of science, Embase, and China national knowledge internet was conducted to identify relevant studies. Pooled odd ratio (OR) and its 95% confidence interval (CI) were computed by STATA version 12.0. Nine case-control studies and one cohort studies comprising 9775 cases and 952,211 controls were included in this study. A positive association between maternal autoimmune diseases and the risk of ASD in offspring was identified assuming a fixed effect model (pooled OR, 1.34; 95% CI, 1.23–1.46; I2, 27.9%). There were statistically significant associations between maternal autoimmune diseases developed during pregnancy or maternal thyroid disease and the risk of ASD in offspring (pooled OR, 1.30, 1.29, respectively). Maternal autoimmune disease is likely to be an independent risk factor of ASD in offspring.