Antimicrobial Prophylaxis Recommended for All Cesarean Deliveries

A new report recommends antimicrobial prophylaxis within 60 minutes of delivery in all cases of cesarean section, unless the patient is already receiving appropriate antibiotic treatment for other conditions.

The recommendation, by the committee on obstetric practice of the American College of Obstetricians and Gynecologists (ACOG; Washington DC, USA), is based on surgical research data that shows that antimicrobial prophylaxis to prevent surgical site infection should ideally begin within 30 minutes, and definitely within 2 hours, of skin incision. For longer surgery, the same dose of antibiotic may need to be given again at intervals of one or two times the half-life of the drug. The committee found that preoperative antibiotic administration significantly reduces endometritis and total maternal infectious morbidity, compared with administration of antibiotics after umbilical cord clamping.

The committee added that all studies to date suggest that preoperative antimicrobial prophylaxis does not appear to have any harmful effect on the mother or infant, nor is it associated with an increase in neonatal infectious morbidity or the selection of antimicrobial-resistant bacteria causing neonatal sepsis. The ACOG committee opinion report was published in the September 2010 issue of Obstetrics and Gynecology.

"Antimicrobial prophylaxis for cesarean delivery has been a general practice for cesarean deliveries because it significantly reduces postoperative maternal infectious morbidity,” concluded William Henry Barth Jr., M.D., chair of the Committee on Obstetric Practice, and colleagues of the committee. "These antibiotics have been administered intraoperatively after umbilical cord clamping for two theoretic concerns related to the fetus; antibiotics in neonatal serum may mask newborn positive bacterial culture results; and fetal antibiotic exposure could lead to an increase in newborn colonization or infection with antibiotic-resistant organisms.”

Antimicrobial prophylaxis for cesarean delivery typically employs narrow-spectrum antibiotics, such as a first-generation cephalosporin, effective against gram-positive bacteria, gram-negative bacteria, and some anaerobic bacteria. A single 1-gram intravenous dose of cefazolin usually results in a therapeutic level for 3 to 4 hours, but obese women may need larger doses.

Clindamycin with gentamicin is a reasonable option for women with a significant allergy to β-lactam antibiotics, such as cephalosporins and penicillins.

Related Links:
American College of Obstetricians and Gynecologists