title: Managed care market share and cesarean section rates in the United States: is there a link?
abstract: OBJECTIVE
  After peaking during the early 1980s, cesarean section rates in the United States have been falling for the last decade. At the same time, managed care enrollment has increased dramatically. This study examines whether managed care penetration in local markets is associated with lower cesarean section rates in those geographic area.
  
  
  METHODS
  A cross-sectional comparison of cesarean section rates and health maintenance organization (HMO) market penetration in 61 selected metropolitan areas in the United States was conducted. National birth certificate data for 1996 were used to calculate crude and race-adjusted cesarean section rates for residents in each area.
  
  
  RESULTS
  No relationship between overall cesarean section rates in the metropolitan areas and managed care penetration was observed. Subanalyses of racial groups demonstrated the existence of a weak association between managed care penetration and cesarean section rates for white women (21.2% for the highest quartile of HMO penetration, compared with 19.1% for the lowest quartile; P = .03), but not for African-Americans or other minorities.
  
  
  CONCLUSIONS
  Managed care penetration in a market may have an association with cesarean section rates for white women, but the strength of this relationship is small. Even if managed care delivery systems reduce cesarean section rates in their own populations, this change is likely to have only a small impact on overall cesarean rates. HMO penetration is unlikely to influence national cesarean section rates, nor does it appear to explain state variations in these rates.
authors.affiliation: Department of Family Medicine, Medical University of South Carolina, Charleston 29425, USA. huestowj@musc.edu
authors.forename: W J
authors.initials: WJ
authors.lastname: Hueston
authors.forename: A
authors.initials: A
authors.lastname: Sutton
mesh_terms: D002585:Cesarean Section / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D005260:Female; D019981:Health Care Sector; D006801:Humans; D008329:Managed Care Programs / Q000191:economics / Q000706:statistics & numerical data*; D011247:Pregnancy; D014481:United States / Q000453:epidemiology; D014600:Utilization Review