1: Post-operative prophylactic oral antibiotics for preventing surgical site infections in obese women undergoing cesarean deliveries: A randomized controlled trial


      To evaluate if prophylactic oral antibiotics following cesarean delivery prevent surgical site infections (SSI) in obese women.

      Study Design

      We performed a single center, randomized double-blinded placebo-controlled trial comparing SSI in obese women (pre-pregnancy BMI ≥30 kg/m2) undergoing cesarean deliveries between 9/2010-12/2015. Participants were randomized to prophylactic antibiotics (cephalexin plus metronidazole) versus placebo for a total of 48 hours following delivery. Women were excluded if they had chorioamnionitis, immunosuppression or planned administration of postpartum antibiotics. Randomization was stratified by amniotic membrane status; intact versus ruptured (ROM). SSI was defined as incisional (superficial or deep tissue), organ, or space infections within 30 days of delivery. Logistic regression was used to determine the relative risk of SSI between women who received antibiotics compared to placebo, and the number needed to treat to prevent one SSI was calculated.


      Of the 405 women enrolled, 203 received oral antibiotics and 202 received placebo. A total of 5.7% (n=22) were loss to follow up with 383 women included for analysis. Maternal demographic and medical characteristics were not significantly different between the two study groups. The overall rate of SSI was 11.7%. The rate of SSI was higher in women with ROM, 21.0%, compared to those with intact membranes, 7.2%. A prophylactic course of antibiotics significantly reduced the risk of SSI in all participants by approximately 60%; RR 0.37 (95% CI 0.19-0.73). A more significant reduction was seen in women with ROM prior to cesarean delivery, RR 0.22 (95% CI 0.08-0.61), versus a non-significant reduction in those with intact membranes, RR 0.56 (95% CI 0.21-1.47). The number needed to treat to prevent one SSI was 10 for all obese women undergoing cesarean delivery and 4 among those with ROM prior to delivery.


      Obese women who undergo cesarean delivery have high rates of SSI, particularly those with ROM prior to delivery. Our study demonstrates that administration of a 48 hour course of prophylactic post-cesarean oral antibiotics decreases the rate of SSI in obese women and should be considered for this high risk population.
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