State Public Coverage of Pregnant Undocumented Immigrants and Prenatal Insurance Uptake.

Policy Points Twenty-four states and the District of Columbia offer public insurance to pregnant undocumented immigrants who are income eligible for Medicaid. We found that residing in a state with public coverage of pregnant undocumented immigrants was associated with increased prenatal Medicaid coverage among immigrants and was not associated with corresponding reductions in private or other insurance coverage. Offering state public insurance to pregnant undocumented immigrants could increase immigrants' access to insurance coverage and recommended care during pregnancy.

Context: Health insurance coverage increases access to recommended pregnancy care, but undocumented immigrants are not eligible for pregnancy Medicaid coverage without state uptake of alternative policy options. Twenty-four states and the District of Columbia (DC) offer public insurance to undocumented immigrants who are income eligible for pregnancy Medicaid through the Children's Health Insurance Program From-Conception-to-End-of-Pregnancy option or state funds. Our objective was to examine the association between residing in a state with public insurance coverage for pregnant undocumented immigrants and prenatal insurance coverage among low-income immigrants.

Methods: We used 2016 to 2021 Pregnancy Risk Assessment Monitoring System responses linked to maternal nativity from birth certificate records from 19 states and DC. We compared the prevalence of any insurance, Medicaid insurance, and private or other insurance coverage of prenatal care between Medicaid income-eligible immigrants and nonimmigrants. We then estimated the association between state public coverage policy and prenatal insurance coverage among immigrants using linear regression models.

Findings: The study included 47,370 adults (13,271 immigrants and 34,099 nonimmigrants) who were income eligible for pregnancy Medicaid. In the ten included states with public coverage of pregnant undocumented immigrants, the proportion of immigrants with any insurance for prenatal care was 16.9 percentage points higher (95% CI, 14.9-18.9) compared with the proportion of immigrants in states without such coverage. In policy-adopting states, the proportion of immigrants with Medicaid for prenatal care was also 16.9 percentage points higher (95% CI, 14.1-19.7) compared with immigrants in nonpolicy-adopting states. We did not find differences by state coverage policy in having had private insurance coverage for prenatal care.

Conclusions: Providing state public insurance coverage to undocumented immigrants during pregnancy may increase overall prenatal insurance coverage by expanding access to Medicaid. We did not find evidence that extending public coverage to this population crowds out other insurance options.