Medicaid Coverage and Postpartum Opioid Use Disorder Treatment

• In Event: From Taxes to Treatment: Policy Approaches to Substance Use and Maternal and Child Health

Abstract

Research Question
What is the causal effect of extending postpartum Medicaid coverage from 60 days to 12 months on MOUD continuation among birthing parents with prenatal treatment?

Background and Policy Relevance
Postpartum overdose is a leading cause of maternal mortality, yet U.S. policy historically imposes a sharp Medicaid eligibility cutoff at 60 days after delivery. The COVID-19 Public Health Emergency (PHE) abruptly suspended Medicaid redeterminations nationwide, converting this cliff into 12 months of continuous coverage. This discrete, externally imposed change isolates coverage continuity as a policy lever and directly informs the now-permanent federal option for 12-month postpartum Medicaid eligibility.

Data and Methods
We use national all-payer claims (IQVIA, 2019–2022) linking medical and pharmacy data for birthing parents ages 18–50 with prenatal MOUD use. Identification relies on a difference-in-differences design comparing Medicaid-financed births (exposed to the policy) to commercially insured births (unexposed) before and after January 2020. The design exploits a sharp, nationwide eligibility expansion that affects postpartum coverage only for Medicaid births. Outcomes are months of MOUD use, continuation beyond 60 days, and adherence (proportion of days covered). Models include state and delivery-month fixed effects and individual controls. Event studies show no differential pre-trends.

Findings
Extended coverage increases Medicaid-financed MOUD by 0.79 months (12.6%) and adherence by 0.058 (12.8%). Net effects on overall MOUD are smaller but positive: a 0.55-month increase (8.0%) and 4–7% gains in continuation and adherence. The divergence between payer-specific and overall effects indicates partial substitution across payers but limited crowd-out of treatment. Effects are concentrated in non-expansion states and in states without paid sick leave mandates, where alternative coverage is least available.

Conclusions
A sharp extension of Medicaid eligibility causally increases treatment continuity in the postpartum period, identifying coverage continuity as a first-order determinant of MOUD retention.

Implications for Policy and Practice
Twelve-month postpartum Medicaid coverage is an effective, scalable mechanism to sustain addiction treatment. Effects are largest where baseline coverage gaps are greatest, implying that federal eligibility policy and state policy environments interact. Reducing administrative frictions and integrating MOUD into perinatal care are likely to amplify these gains.

Author

• Sumedha Gupta, Indiana University
  Presenting Author