title: Nonclinical parameters affecting primary cesarean rates in the United States.
abstract: OBJECTIVE
  Cesarean is the single most common operation in United States and has reached epidemic proportions in recent decades. Our objective was to study the effect of nonclinical parameters on primary cesarean rates in a large contemporary population.
  
  
  METHODS
  We designed a retrospective multicenter study using data obtained from electronic medical records from 19 U.S. hospitals between 2005 and 2007 (Consortium on Safe Labor Database), which included 145,764 term, singleton, nonanomalous, vertex, live births that included labor. The impact of nonclinical parameters (patient and provider characteristics, time of delivery, institutional policies, and insurance type) was investigated using modified Poisson regression methodology and classification and regression tree analysis.
  
  
  RESULTS
  There were 125,517 vaginal and 20,247 cesarean deliveries. Using the multivariable model, the nonclinical parameters with statistical significance for primary cesarean were delivery during evening hours, a male provider, public insurance, and nonwhite race (p < 0.001).
  
  
  CONCLUSIONS
  Cesarean rates are associated with several nonclinical factors. Further investigation into these factors might help to develop strategies to reduce their influence and hence the rates of cesarean.
authors.affiliation: Department of Obstetrics and Gynecology, Maimonides Medical Center, Brooklyn, New York.
authors.forename: Shoshana
authors.initials: S
authors.lastname: Haberman
authors.affiliation: Department of Obstetrics and Gynecology, Maimonides Medical Center, Brooklyn, New York.
authors.forename: Sumit
authors.initials: S
authors.lastname: Saraf
authors.affiliation: MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Obstetrics and Gynecology, Georgetown University Hospital, MedStar Health, Washington, District of Columbia.
authors.forename: Helain J
authors.initials: HJ
authors.lastname: Landy
authors.affiliation: Intermountain HealthCare and University of Utah, Salt Lake City, Utah.
authors.forename: D W
authors.initials: DW
authors.lastname: Branch
authors.affiliation: Baystate Medical Center, Springfield, Massachusetts.
authors.forename: Ronald
authors.initials: R
authors.lastname: Burkman
authors.affiliation: Department of Obstetrics and Gynecology, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Kimberly D
authors.initials: KD
authors.lastname: Gregory
authors.affiliation: Department of Obstetrics and Gynecology Texas Children's Hospital, University of Texas Health Science Center at Houston, Houston, Texas.
authors.forename: Mildred M
authors.initials: MM
authors.lastname: Ramirez
authors.affiliation: MetroHealth Medical Center, Cleveland, Ohio.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Bailit
authors.affiliation: Department of Obstetrics and Gynecology, University of Miami, Miami, Florida.
authors.forename: Victor H
authors.initials: VH
authors.lastname: Gonzalez-Quintero
authors.affiliation: Department of Obstetrics and Gynecology, University of Illinois at Chicago, Chicago, Illinois.
authors.forename: Judith U
authors.initials: JU
authors.lastname: Hibbard
authors.affiliation: Christiana Care Health System, Wilmington, Delaware.
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Hoffman
authors.affiliation: Department of Obstetrics and Gynecology, University of Illinois at Chicago, Chicago, Illinois.
authors.forename: Michelle
authors.initials: M
authors.lastname: Kominiarek
authors.affiliation: The EMMES Corporation, Rockville, Maryland.
authors.forename: Li
authors.initials: L
authors.lastname: Lu
authors.affiliation: The EMMES Corporation, Rockville, Maryland.
authors.forename: Paul
authors.initials: P
authors.lastname: Van Veldhuisen
authors.affiliation: Summa Health System, Akron City Hospital, Akron, Ohio.
authors.forename: Vivian
authors.initials: V
authors.lastname: Von Gruenigen
mesh_terms: D002585:Cesarean Section / Q000706:statistics & numerical data*; D015986:Confounding Factors, Epidemiologic; D036861:Delivery, Obstetric / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009774:Obstetrics; D011247:Pregnancy; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States