BACKGROUND AND PURPOSE:

• Evidence is limited as to whether antibiotics are beneficial for operative deliveries
• Knight et al. (Lancet, 2019) investigated whether antibiotic prophylaxis was effective at preventing maternal infection following operative vaginal birth

METHODS:

• Blinded, randomized controlled trial (RCT)
  • Prophylactic ANtibiotics in the prevention of infection after Operative vaginal DElivery (ANODE) trial
• Participants
  • ≥16 years who had undergone operative vaginal birth at ≥36 weeks
  • Any type of operative delivery included
    • Any type of instrument
    • Whether or not rotation used
    • Any station of the fetal head at the time of instrument application
• Exposure
  • Single dose IV: 1 g amoxicillin and 200 mg clavulanic acid
  • Administered as soon as possible and no more than 6 h after giving birth
• Primary outcome
  • Confirmed or suspected maternal infection within 6 weeks of delivery defined by
    • A new prescription of antibiotics for perineal wound infection | UTI | Confirmed systemic infection on culture | Endometritis
• Secondary outcomes included
  • Systemic sepsis | perineal wound infection | Perineal pain | Use of pain relief | Length of stay | Need for additional perineal care | Dyspareunia
  • Antibiotic side effects
  • Healthcare costs
• Analysis
  • To detect 50% difference with 90% statistical power, 1,712 women would be required per arm if taking in to account a 5% loss to follow-up
  • Intention-to-treat analysis

RESULTS:

• 3,420 women
  • 1,715 in antibiotic group | 1,705 in placebo group
  • Primary outcome data were missing for 6% of women (195 women)
• Significantly fewer women in the amoxicillin and clavulanic acid group had confirmed or suspected infection
  • 11% of amoxicillin and clavulanic acid group
  • 19% of placebo group
  • Risk ratio (RR) 0.58, (95% CI, 0.49–0.69; p<0.0001)
• Intervention benefit was also seen at 6 weeks post-delivery with significantly lower proportion of women affected with the following secondary outcomes
  • Perineal infection | Perineal pain | Use of pain relief for perineal pain | Need for additional perineal care | Wound breakdown
• Post-hoc analysis looking at forceps and vacuum separately
  • In both forceps and vacuum, number of women with infection was reduced by approximately 50%
• Adverse reactions
  • Amoxicillin and clavulanic acid: 2 women had allergic reactions, one serious
  • Placebo: 1 woman had a skin rash
  • Two other serious adverse events were reported, but neither was considered to be caused by the treatment

CONCLUSION:

• Antibiotic prophylaxis reduced risk of maternal infection following operative vaginal birth
• The authors conclude

…this trial shows clear benefit of a single dose of prophylactic antibiotic after operative vaginal birth, and guidance should be changed to reflect this finding.

Learn More – Primary Sources:

Prophylactic antibiotics in the prevention of infection after operative vaginal delivery (ANODE): a multicentre randomised controlled trial

Related ObG Topics:

Cesarean Delivery Best Practices & Guidelines – The ERAS Committee Recommendations

Forceps/Vacuum Delivery vs Cesarean Section and Adverse Maternal and Perinatal Outcomes

Mode of Delivery and Risk of Pelvic Floor Disorders, Quantified Over Time

Azithromycin Prophylaxis to Reduce Infection Risk Post C-Section