title: Risk of selected postpartum infections after cesarean section compared with vaginal birth: a five-year cohort study of 32,468 women.
abstract: OBJECTIVE
  To compare the risk of postpartum infections within 30 days after vaginal birth, emergency, or elective cesarean section (CS).
  
  
  METHODS
  Register-based cohort study in Denmark.
  
  
  METHODS
  A total of 32,468 women giving birth in hospitals in the County of Aarhus, Denmark, during the period 2001-2005.
  
  
  METHODS
  Data from various hospital registries were combined and infections were identified by positive cultures, prescriptions for antibiotics and, re-operative procedures.Risk of postpartum infection was estimated and adjustment for potentially confounders was performed.
  
  
  RESULTS
  Within 30 days postpartum, 7.6% of women who had underwent CS and 1.6% of women having a vaginal birth acquired an infection, yielding an adjusted odds ratio (OR) of 4.71, 95% confidence interval (CI): 4.08-5.43. The prevalence of postpartum urinary tract infection (UTI) was 2.8%, after CS and 1.5% after vaginal birth corresponding to an adjusted OR = 1.68, 95% CI: 1.38-2.03. The risk of UTI did not differ between emergency and elective CS. The prevalence of WI was 5.0% after CS and 0.08% after vaginal birth. Moreover, we found a nearly 50% higher risk of postpartum WI after emergency CS compared to elective CS (OR = 1.49, 95% CI: 1.13-1.97). More than 75% (697/907) of postpartum infections appeared after hospital discharge.
  
  
  CONCLUSIONS
  The risk of postpartum infection seems to be nearly five-fold increased after CS compared with vaginal birth. This may be of concern since the prevalence of CS is increasing.
authors.affiliation: Department of Clinical Microbiology, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, 8200 Aarhus N, Denmark. ritaleth@rm.dk
authors.forename: Rita Andersen
authors.initials: RA
authors.lastname: Leth
authors.forename: Jens Kjølseth
authors.initials: JK
authors.lastname: Møller
authors.forename: Reimar Wernich
authors.initials: RW
authors.lastname: Thomsen
authors.forename: Niels
authors.initials: N
authors.lastname: Uldbjerg
authors.forename: Mette
authors.initials: M
authors.lastname: Nørgaard
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000009:adverse effects*; D015331:Cohort Studies; D036861:Delivery, Obstetric / Q000379:methods*; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D007239:Infections / Q000453:epidemiology*; D016017:Odds Ratio; D049590:Postpartum Period; D011247:Pregnancy; D015995:Prevalence; D012042:Registries / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012306:Risk; D013530:Surgical Wound Infection / Q000453:epidemiology; D014552:Urinary Tract Infections / Q000453:epidemiology*; D055815:Young Adult