Linking State Medicaid Data and Birth Certificates For Maternal Health Research

Medicaid pays for nearly half of all live births in the United States. Women and infants covered by Medicaid typically live in households with lower incomes, have more complex medical needs, and bear a disproportionate burden of maternal mortality and poor infant health outcomes compared with women and infants with private insurance. Mothers' Medicaid data, which includes enrollment and eligibility information, and claims and encounter data (hereafter "claims"), linked with infant birth certificates (hereafter "birth certificates") hold the potential to be a vital source of data for maternal and infant health research. While Medicaid claims data contain key information on diagnosis and service utilization for pregnant individuals, birth certificates often contain information on pregnancy outcomes not captured or incompletely captured in these claims. Despite the utility of linked Medicaid and birth certificate data, performing such linkages across different states and multistate maternal health research with these data poses challenges. Each state administers its own Medicaid program, and states vary widely in the types of data that are linked to Medicaid claims and the methods for these linkages. Researchers who want to use multistate linked data must obtain them separately from each state, and the data obtained may not be comparable due to the different data linkage methodologies used by states.