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Immigration, Pregnancy, and Heath Insurance: New Evidence and Ongoing Debate

Daw, Jamie R. MSc; Sommers, Benjamin D. MD, PhD

doi: 10.1097/AOG.0000000000002338
Contents: Editorial

Ms. Daw is from the Department of Health Care Policy at Harvard Medical School, Boston, Massachusetts; email: Dr. Sommers is from the Harvard T. H. Chan School of Public Health and Brigham & Women's Hospital; Boston, Massachusetts; email:

Financial Disclosure The authors did not report any potential conflicts of interest.

Jamie R

Jamie R

Benjamin D

Benjamin D

Approximately 1 in 15 children born in the United States are born to undocumented immigrant parents.1 Despite consensus that prenatal care is critical to supporting maternal and infant health, undocumented women are significantly less likely to have adequate prenatal care compared with U.S. citizens.2 In part, this reflects high uninsured rates in this population (42% in 2015) due to economic barriers to employer-sponsored coverage and restrictions on federal Medicaid spending for undocumented immigrants.3 Although emergency Medicaid covers the costs of labor and delivery for low-income women regardless of immigration status, it does not cover prenatal or postpartum care.

In 2002, the Children's Health Insurance Program added an “unborn child” option to cover undocumented pregnant women, and the 2009 Children's Health Insurance Program Reauthorization Act allowed states to use federal funding to provide coverage for prenatal, delivery, and postpartum care regardless of immigration or legal status. Even after the Affordable Care Act (ACA), these remain the only federal coverage options available for unauthorized and recently immigrated pregnant women. Yet, as of January 2015, only 16 states have adopted the unborn child option and only 22 have expanded coverage to cover pregnant recently arrived legal immigrants.4

In this issue of Obstetrics & Gynecology, Swartz and colleagues (see page 938) evaluate Oregon's implementation of Emergency Medicaid Plus, which expanded coverage to pregnant undocumented and recent legal immigrants.5 The authors draw on rich claims data and apply a rigorous, quasi-experimental study design (differences-in-differences) that exploits the staggered roll-out of the program across counties from 2008 to 2013. They found that the coverage expansion was associated with a significant increase in prenatal care use and fetal ultrasound examinations and a significant decrease in infant mortality and extremely low birth weight.

Swartz et al further found that covering mothers during pregnancy was associated with increased well-child visits and vaccination rates among children during the first year of life. This provides suggestive evidence that the benefits of pregnancy-related coverage expansion extend beyond delivery and into the early childhood years. These findings are consistent with other studies showing that expanding coverage to parents has positive spillover effects for children.6,7

The study joins two recent analyses that used national data and similar study designs to examine state-level expansions of Emergency Medicaid.4,8 These prior studies also found increased prenatal care, which was concentrated among mothers with low levels of education. However, neither found significant effects on infant health outcomes, which raised the question of whether prenatal care may be “too little too late” to improve birth outcomes for this population.

In this context, the reductions in very low birth weight and infant mortality in the Schwartz study provide encouraging new evidence. However, given the conflicting evidence from previous national studies, more research is needed to corroborate these findings. The validity of the difference-in-differences approach in Oregon relies on the assumption that the postexpansion trends in the Emergency Medicaid and Standard Medicaid groups would have been similar if not for the introduction of Emergency Medicaid Plus. The authors do not offer formal tests of the differences in pre-expansion trends, which could have provided additional evidence that the observed changes were solely from the policy rather than a result of other, unmeasured factors changing over time. The lack of data on prenatal care received by uninsured women is also an important limitation of using only Medicaid claims, and thus the study likely overstates the effects of expanding Emergency Medicaid Plus on utilization.

Finally, it is unclear whether the findings from Oregon, which has relatively few unauthorized immigrants, are generalizable to states such as California and Texas, which together account for approximately 40% of the unauthorized immigrant population in the United States. Nonetheless, the study provides valuable new evidence on an important topic. Understanding the extent to which coverage alone can improve pregnancy-related outcomes is critical to evaluating coverage expansion compared with other investments such as upstream risk-factor management or intensive home-visiting.

This timely study has the potential to inform several important policy debates. First, Congress must decide whether to reauthorize funding for the Children's Health Insurance Program (CHIP), which expired on September 30, 2017. At the time of this writing, it is unclear when or whether CHIP will be reauthorized, and if so, whether it will include the unborn child option. If CHIP funds are not renewed, the loss of health insurance among millions of near-poor and midde-income children could be devastating to children's health. In addition to taking action to avert this potential widespread loss of children's coverage, Congress should also consider extending CHIP's unborn child option, given Swartz and colleagues' findings. If the unborn child option is not continued, many immigrant women will have no option for coverage before, during, or after pregnancy, potentially harming both immigrant mothers and their newborn children (who are U.S. citizens), an outcome whose harmful effects will be magnified if CHIP coverage ceases to exist more broadly.

Second, this evidence intersects with current debates over immigration policy in the United States. Even in states that have programs designed to improve the health of undocumented immigrant mothers and children, uncertainty over immigration policy and the increased threat of deportation under the new administration may have a chilling effect on enrollment. Previous research has shown that heightened federal immigration enforcement reduces Medicaid participation even among eligible applicants.9

Finally, this study connects to a wider discussion about public coverage for pregnant women in the United States. As with standard pregnancy-related Medicaid, expanded Emergency Medicaid programs cover women only from conception to 60 days after delivery. This time-limited coverage is associated with frequent changes between uninsurance and Medicaid in the preconception and postpartum period, which disrupts continuity of care and may reduce the effectiveness of prenatal care.10 Although the ACA's Medicaid expansions and Marketplaces offer new options that should improve continuity of coverage for pregnant women, these options remain unavailable to undocumented women and some recent immigrants. Even among U.S. citizens, for those living in the 19 states that did not expand Medicaid under the ACA, time-limited, pregnancy-related Medicaid is the only option for many low-income women. Given established consensus about the importance of chronic disease management, risk-factor prevention, and postpartum care, we ought to reconsider whether providing coverage for only a brief snapshot of a woman's reproductive life is the right approach for promoting the health of women, children, and families.

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© 2017 by The American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. All rights reserved.