Exhibit 4.

Mean number of Medicaid-financed outpatient visits in the six months after delivery in Colorado and Utah, January 2013-June 2015

SOURCE Authors’ analysis of data for 2013–15 from all-payer claims databases in Colorado and Utah. NOTES The shaded area highlights deliveries occurring during July–December 2013. These deliveries were treated as transitional in our models because the six-month postpartum periods for deliveries occurring during July–December 2013 extended beyond the date of Colorado’s Medicaid expansion on January 1, 2014. In a test for difference of January–June 2013 trends across states, β = −0.00 and p = 0.243.