Background <p>Emergency department (ED) use is common among patients with Medicaid insurance during pregnancy. However, it is unknown how ED utilization differs among those with different types of Medicaid such as Emergency Medicaid, with which access to outpatient care is more restricted.</p> Objective <p>We sought to compare differences in ED use during between pregnant persons with Emergency Medicaid and Traditional Medicaid and pregnancy outcomes by ED utilization.</p> Study design <p>This was a retrospective cohort study of all births among Medicaid enrollees in South Carolina from 2010 to 2019. The main comparator was type of Medicaid. Our primary outcome was an ED visit during pregnancy. Secondary outcomes included average number of visits, perinatal outcomes, and prenatal and hospital charges.</p> Results <p>There were 240,597 births that met inclusion criteria for this analysis. Over the study period, the proportion of patients with at least one ED visit increased for all groups. A higher proportion of patients with Traditional Medicaid had at least one ED visit compared with Emergency Medicaid (58.2% versus 22.7%). Patients who had at least one ED visit were more likely to be younger, of Black race, live rurally, nulliparous, have lower or higher body mass index, and have a higher prevalence of pre-existing medical co-morbidities.</p> Conclusion <p>We found that individuals with Traditional Medicaid were more likely to have an antenatal ED visit than individuals with Emergency Medicaid.</p>