Medicaid-funded obstetric care coordination programs supplement prenatal care with tailored services to improve birth outcomes. It is uncertain whether these programs reach populations with elevated risks of adverse birth outcomes-namely non-white, highly rural, and highly urban populations. This study evaluates racial and geographic variation in the receipt of Wisconsin Medicaid's Prenatal Care Coordination (PNCC) program during 2010-2019. We sample 250,596 Medicaid-paid deliveries from a cohort of linked Wisconsin birth records and Medicaid claims. We measure PNCC receipt during pregnancy dichotomously (none; any) and categorically (none; assessment/care plan only; service receipt), and we stratify the sample on three maternal characteristics: race/ethnicity, urbanicity of residence county; and region of residence county. We examine annual trends in PNCC uptake and conduct logistic regressions to identify factors associated with assessment or service receipt. Statewide PNCC outreach decreased from 25% in 2010 to 14% in 2019, largely due to the decline in beneficiaries who only receive assessments/care plans. PNCC service receipt was greatest and persistent in Black and Hispanic populations and in urban areas. In contrast, PNCC service receipt was relatively low and shrinking in American Indian/Alaska Native, Asian/Pacific Islander, and white populations and in more rural areas. Additionally, being foreign-born was associated with an increased likelihood of getting a PNCC assessment in Asian/Pacific Islander and Hispanic populations, but we observed the opposite association in Black and white populations. Estimates signal a gap in PNCC receipt among some at-risk populations in Wisconsin, and findings may inform policy to enhance PNCC outreach.