title: A national estimate of the elective primary cesarean delivery rate.
abstract: OBJECTIVE
  We describe national trends for elective primary cesarean delivery from 1994 to 2001, with attention to changes in indications.
  
  
  METHODS
  We used data from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample. Cesarean deliveries were identified by International Classification of Diseases, 9th Revision, Clinical Modification procedure and diagnostic codes; V codes identified all types of deliveries for denominators. Twelve indications for elective primary cesarean delivery were targeted. International Classification of Diseases, 9th Revision, Clinical Modification coding changes were also evaluated.
  
  
  RESULTS
  After excluding women who had labored and previous cesarean deliveries, elective primary cesarean deliveries rose from 19.7% of all cesarean deliveries in 1994 to 28.3% in 2001, an increase of approximately 43.6%. The use of the identified indications for elective primary cesarean delivery increased for codes representing malpresentation, antepartum bleeding, hypertension and severe hypertension, macrosomia, unengaged head, preterm gestation, and maternal soft tissue disorders. Coding for herpes, multiple gestation, other uterine scar, and congenital central nervous system remained the same. Additionally, a new 1998 code for fetal heart rate abnormalities was rapidly adopted during the study period.
  
  
  CONCLUSIONS
  A national estimate of the elective primary cesarean delivery rate shows a rising trend. Additionally, coded indications for these procedures are shifting. Further examination into the use and clinical implications of indications through national surveillance for elective primary cesarean delivery is important for future obstetric practice. A revision of the terminology classification used to identify indications for cesarean delivery procedures would aid in this effort.
  
  
  METHODS
  III.
authors.affiliation: Agency for Healthcare Research and Quality, Rockville, MD 20850, USA. smeikle@ahrq.gov
authors.forename: Susan F
authors.initials: SF
authors.lastname: Meikle
authors.forename: Claudia A
authors.initials: CA
authors.lastname: Steiner
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: William L
authors.initials: WL
authors.lastname: Lawrence
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000706:statistics & numerical data*; D003953:Diagnosis-Related Groups / Q000706:statistics & numerical data; D017558:Elective Surgical Procedures / Q000706:statistics & numerical data*; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D007744:Obstetric Labor Complications / Q000453:epidemiology* / Q000209:etiology / Q000601:surgery*; D011247:Pregnancy; D014481:United States / Q000453:epidemiology; D014600:Utilization Review