January 5, 2018 CNN
Research by Emily Oster is cited about the infant mortality rate in the United States. "In the paper, published in the American Economic Journal: Economic Policy, 'we find that 45% of regional differences can be attributed to differences in birth weight, with lower birth weights in states like Oklahoma, Arkansas, Louisiana, and Texas, especially relative to the Northeast.'"
These are the states where infant mortality is highest (research by Emily Oster cited) – CNN