Administration of cefazolin prior to skin incision is superior to cefazolin at cord clamping in preventing postcesarean infectious morbidity: a randomized, controlled trial

Am J Obstet Gynecol. 2007 May;196(5):455.e1-5. doi: 10.1016/j.ajog.2007.03.022.


Objective: The objective of the study was to determine whether the administration of cefazolin prior to skin incision was superior to administration at the time of umbilical cord clamping for the prevention of postcesarean infectious morbidity.

Study design: This was a prospective, randomized, double-blind, placebo-controlled trial. Study subjects received cefazolin 15-60 minutes prior to incision and controls received cefazolin at the time of cord clamping. The occurrence of endomyometritis, wound infection, total infectious morbidity, and neonatal complications were compared.

Results: There were 357 subjects enrolled. No demographic differences were observed between groups. There were decreased total infectious morbidity in the study group (relative risk [RR] = 0.4, 95% confidence interval [CI] 0.18 to 0.87), decreased endometritis (RR = 0.2, 95% CI 0.15 to 0.94). No increase in neonatal sepsis (P = .99), sepsis workups (P = .96), or length of stay (P = .17) was observed.

Conclusion: Administration of prophylactic cefazolin prior to skin incision resulted in a decrease in both endomyometritis and total postcesarean infectious morbidity, compared with administration at the time of cord clamping. This dosing did not result in increased neonatal septic workups or complications.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-Bacterial Agents / administration & dosage*
  • Antibiotic Prophylaxis
  • Bacterial Infections / prevention & control*
  • Cefazolin / administration & dosage*
  • Cesarean Section*
  • Constriction
  • Double-Blind Method
  • Endometritis / prevention & control
  • Female
  • Humans
  • Postoperative Complications
  • Pregnancy
  • Prospective Studies
  • Sepsis / prevention & control
  • Surgical Wound Infection / prevention & control
  • Time Factors
  • Umbilical Cord / surgery


  • Anti-Bacterial Agents
  • Cefazolin