Background <p>Dental care before pregnancy is critical for preventing poor oral health, which is associated with adverse pregnancy outcomes. People with low incomes, however, may face insurance-related barriers to obtaining dental care. Medicaid expansion under the Affordable Care Act increased access to dental care utilization among adults with low incomes. However, little is known about the impact of Medicaid policies on pre-pregnancy dental care utilization.</p> Objective <p>To evaluate the impacts on pre-pregnancy dental care utilization of two aspects of Medicaid policy: (1) state level of Medicaid dental coverage and (2) Medicaid expansion overall and by state level of dental coverage.</p> Methods <p>We used data from Pregnancy Risk Assessment Monitoring System (PRAMS) data phases 7 (2012–15) and 8 (2016–18). To examine the association between state level of dental coverage beyond emergency services (i.e., extensive vs. limited) and pre-pregnancy dental care utilization, we conducted an adjusted logistic regression analysis. To evaluate the impact of Medicaid expansion on pre-pregnancy dental care utilization, we conducted a quasi-experimental event study design, which estimates the percentage point difference in the outcome between expansion and non-expansion states at each time period compared to the period just prior to Medicaid expansion.</p> Results <p>We found a significant 13% (adjusted odds ratio (OR) = 1.13; 95% CI: 1.05, 1.22) higher odds of pre-pregnancy dental care utilization among the birthing people residing in states that provided extensive dental coverage compared to those in states that provided limited dental coverage. However, Medicaid expansion under the ACA was not associated with pre-pregnancy dental care utilization overall or among either states with extensive or limited Medicaid dental coverage.</p>