title: Trends in the rate of shoulder dystocia over two decades.
abstract: OBJECTIVE
  To describe the trend in the rate of shoulder dystocia over twenty-four years and identify the risk factors related to the occurrence of dystocia.
  
  
  METHODS
  Data was obtained from Maryland State regarding all vaginal deliveries that occurred during six different time periods at five-year intervals since 1979. Trends in the rate of shoulder dystocia, episiotomy, forceps and vacuum delivery were examined.
  
  
  RESULTS
  There were a total of 277 974 vaginal deliveries. The overall rate of shoulder dystocia was 1.29% (n = 3590). Induction of labor (adjusted OR 1.2, 1.1-1.3), presence of diabetes (gestational (OR 1.9, 1.7-2.3) or pre-gestational (OR 3.8, 2.7-5.4)), fetal macrosomia (OR 5.1, 4.1-6.3) use of episiotomy (OR 1.6, 1.5-1.8), forceps (OR 1.3, 1.0-1.8) or vacuum (OR 2.3, 2.0-3.9) at delivery were associated with a higher rate of shoulder dystocia. TREND: There was an increase in the rate of shoulder dystocia from 0.2% in 1979 to 2.11% in 2003. In addition there was a drop in the overall episiotomy rate from 73.67% to 23.94% and increase in the use of vacuum from 0.1% to 8.36%.
  
  
  CONCLUSIONS
  The rate of shoulder dystocia has increased by 10 fold during the study period. The use of episiotomy either at spontaneous delivery or instrumental delivery does not appear to decrease the occurrence of shoulder dystocia.
authors.affiliation: Department of Obstetrics and Gynecology, Temple University Hospital, Philadelphia, PA 19140, USA. dandolv@tuhs.temple.edu
authors.forename: Vani
authors.initials: V
authors.lastname: Dandolu
authors.forename: Lakesha
authors.initials: L
authors.lastname: Lawrence
authors.forename: John P
authors.initials: JP
authors.lastname: Gaughan
authors.forename: Chad
authors.initials: C
authors.lastname: Grotegut
authors.forename: Ozgur H
authors.initials: OH
authors.lastname: Harmanli
authors.forename: David
authors.initials: D
authors.lastname: Jaspan
authors.forename: Enrique
authors.initials: E
authors.lastname: Hernandez
mesh_terms: D000293:Adolescent; D000328:Adult; D001720:Birth Injuries / Q000453:epidemiology*; D020516:Brachial Plexus Neuropathies / Q000453:epidemiology*; D019992:Databases as Topic; D003920:Diabetes Mellitus / Q000453:epidemiology; D004420:Dystocia / Q000453:epidemiology*; D004841:Episiotomy / Q000009:adverse effects / Q000706:statistics & numerical data / Q000639:trends; D005260:Female; D005320:Fetal Macrosomia / Q000453:epidemiology; D006801:Humans; D007751:Labor, Induced / Q000009:adverse effects / Q000706:statistics & numerical data; D016015:Logistic Models; D008396:Maryland / Q000453:epidemiology; D009772:Obstetrical Forceps / Q000009:adverse effects / Q000706:statistics & numerical data; D011247:Pregnancy; D012307:Risk Factors; D014620:Vacuum Extraction, Obstetrical / Q000009:adverse effects / Q000706:statistics & numerical data / Q000639:trends