OBJECTIVE: To explore the associations between hypertensive disorders of pregnancy and the subsequent development of autoimmune diseases. METHODS: This retrospective cohort study used TriNetX, a federated network of real-world data. Using the Global Collaborative Network data, we collected electronic medical records from 102 health care organizations with 131 million patient records from 2006 to 2020. The study assessed the risk of autoimmune diseases in women aged 16-45 years. Two cohorts were compared: the pregnancy-induced hypertension cohort, which included women with gestational hypertension, preeclampsia, or eclampsia, and the normotensive pregnancy cohort. Women with preexisting autoimmune diseases or hypertension and those with complications occurring before 20 weeks of gestation were excluded. Propensity score matching was used to ensure balanced cohorts. The primary outcome was the long-term risk of autoimmune diseases during a follow-up period of up to 18 years. The secondary outcome evaluated the association between the risk of autoimmune diseases and both the patient's age and the severity of pregnancy-induced hypertension. RESULTS: The prevalence of pregnancy-induced hypertension was found to be 13.4%. After propensity score matching, among 289,564 women, those with pregnancy-induced hypertension demonstrated a significantly higher risk of developing autoimmune diseases during long-term follow-up. The risk of systemic lupus erythematosus was notably higher (hazard ratio 1.87, 95% CI, 1.60-2.18), along with elevated risks of multiple sclerosis, Addison disease, antiphospholipid syndrome, inflammatory bowel disease, mixed connective tissue disease, and rheumatoid arthritis. Subgroup analysis revealed that women of advanced maternal age with pregnancy-induced hypertension had a similar risk of developing autoimmune diseases compared with younger women. In addition, the risk of these autoimmune diseases increased with the severity of pregnancy-induced hypertension. CONCLUSION: Women with a history of pregnancy-induced hypertension face a higher long-term risk of autoimmune diseases, emphasizing the need for ongoing monitoring and preventive care.