Women with SLE, RA, and pregestational DM had significantly increased rates of hypertensive disorders compared with the general obstetric population (23.2%, 11.1%, 27.4%, and 7.8%, respectively), longer hospital stays, and significantly higher risk of cesarean delivery. Although women with SLE, RA, and pregestational DM were significantly older than women in the general obstetric population, disparities in the risk of adverse outcomes of pregnancy remained statistically significant after adjustment for maternal age.