Objectives: In this study, we sought to determine the impact of oral health literacy (OHL) on use of prenatal dental care and knowledge, understanding, and practices related to preventing dental caries (tooth decay) among low-income pregnant women in Maryland. Methods: We conducted a mixed methods study using a survey and a structured guide for one-on-one interviews or focus groups. The study included 117 pregnant women and was conducted between July 2016 and April 2018 in Maryland. Results: Respondents had a low level of OHL. Maryland Medicaid covers prenatal dental care, but only 53% of participants reported seeing a dentist during their pregnancy. Most women were unaware of the Medicaid dental program for pregnant women and the importance of prenatal dental care. They could not afford care if there was an associated cost and had difficulty finding a Medicaid dental provider. Importantly, they lacked understanding of how to prevent caries and did not practice behaviors to prevent this disease. Conclusions: To decrease caries rates, policies and programs must be implemented to increase the OHL of low-income pregnant women because the OHL of caregivers is associated with their children's oral health status.