Geographic Variation in Cesarean Sections in the United States: Trends, Correlates, and Other Interesting Facts
利用三十年全美出生数据，研究首次单胎分娩产妇的剖宫产率在县级层面的持续地理差异，发现高剖宫产率地区产妇和婴儿发病率更低，但黑人产妇的剖宫产决策对风险反应不足，存在福利损失。
Analyzing data spanning three decades covering the near universe of births, we study county-level differences in Cesarean section (C-section) rates among first-time mothers of singleton births. Our research reveals persistent geographic variation in C-section rates for both low- and high-risk groups. Counties with elevated C-section rates consistently perform more C-sections across mothers at all levels of appropriateness for the procedure. These elevated rates of C-section in high C-section counties are associated with reduced maternal and infant morbidity. We also find that C-section decisions are less responsive to underlying risks for Black mothers relative to white mothers, suggesting potential welfare-reducing disparities.