Medicaid Expansion and Birth Outcomes

One of the great successes of the Affordable Care Act has been the expansion of Medicaid. In large part due to this expansion, the number of individuals in the United States with health care coverage has increased by about 25 to 30 million since 2011; following midterm elections, it is likely that additional Medicaid expansion will occur.¹

However, questions have remained regarding whether Medicaid expansion has had a beneficial effect on health outcomes. The study by Brown and colleagues² in this issue of JAMA provides important new data. The study included 15 631 174 births, and compared birth outcomes in 18 states and the District of Columbia that expanded Medicaid with 17 states that did not. Although in difference-in-differences analyses, state Medicaid expansion was not associated with significant differences in rates of preterm birth (6.80% to 6.67% vs 7.86% to 7.78%) or low birth weight (5.41% to 5.36% vs 6.06% to 6.18%) overall, difference-in-difference-in-differences analyses showed that there were significant improvements in disparities for black infants relative to white infants for all 4 outcomes, including preterm birth, very preterm birth, low birth weight, and very low birth weight. These changes are critically important because of long-standing and persistent differences in infant mortality between black and white infants.

This study adds to a growing literature demonstrating improved health outcomes associated with Medicaid expansion, including a previous report in JAMA by Swaminathan et al that detailed the association between Medicaid expansion and lower 1-year mortality among patients with end-stage renal disease initiating dialysis.^3,4

The future of health care coverage in the United States remains uncertain. The current administration has continued to make it more difficult for individuals to obtain health care coverage, and in 2018, the number of uninsured individuals increased for the first time in 7 years. Opponents of further Medicaid expansion argue that the program is too expensive or that it fails to improve health outcomes. The former critique is the source of ongoing policy debate, but the latter is increasingly proving false. In fact, as the study by Brown and colleagues² highlights, Medicaid expansion may be helping to reduce racial disparities in one of the most important health indicators of a society—birth outcomes related to infant mortality.

Corresponding Author: Howard Bauchner, MD, JAMA, 330 N Wabash Ave, Chicago, IL 60611 (howard.bauchner@jamanetwork.org).