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

Abstract

Summary Background Risk factors for maternal infection are clearly recognised, including caesarean section and operative vaginal birth. Antibiotic prophylaxis at caesarean section is widely recommended because there is clear systematic review evidence that it reduces incidence of maternal infection. Current WHO guidelines do not recommend routine antibiotic prophylaxis for women undergoing operative vaginal birth because of insufficient evidence of effectiveness. We aimed to investigate whether antibiotic prophylaxis prevented maternal infection after operative vaginal birth. Methods In a blinded, randomised controlled trial done at 27 UK obstetric units, women (aged ≥16 years) were allocated to receive a single dose of intravenous amoxicillin and clavulanic acid or placebo (saline) following operative vaginal birth at 36 weeks gestation or later. The primary outcome was confirmed or suspected maternal infection within 6 weeks of delivery defined by a new prescription of antibiotics for specific indications, confirmed systemic infection on culture, or endometritis. We did an intention-to-treat analysis. This trial is registered with ISRCTN, number 11166984, and is closed to accrual. Findings Between March 13, 2016, and June 13, 2018, 3427 women were randomly assigned to treatment: 1719 to amoxicillin and clavulanic acid, and 1708 to placebo. Seven women withdrew, leaving 1715 in the amoxicillin and clavulanic acid group and 1705 in the placebo groups. Primary outcome data were missing for 195 (6%) women. Significantly fewer women allocated to amoxicillin and clavulanic acid had a confirmed or suspected infection (180 [11%] of 1619) than women allocated to placebo (306 [19%] of 1606; risk ratio 0·58, 95% CI 0·49–0·69; p<0·0001). One woman in the placebo group reported a skin rash and two women in the amoxicillin and clavulanic acid reported other allergic reactions, one of which was reported as a serious adverse event. Two other serious adverse events were reported, neither was considered causally related to the treatment. Interpretation This trial shows benefit of a single dose of prophylactic antibiotic after operative vaginal birth and guidance from WHO and other national organisations should be changed to reflect this. Funding NIHR Health Technology Assessment programme.

Assisted Vaginal Birth

“…The ANODE trial was a multicentre, randomised, blinded, controlled trial done at 27 hospital obstetric units in the UK. 133 Women who had undergone birth by forceps or vacuum at 36 weeks or greater gestation, with no indication for ongoing prescription of antibiotics in the postpartum period and no contraindications to prophylactic amoxicillin and clavulanic acid, were randomly assigned (1:1) to receive a single intravenous dose of prophylactic amoxicillin and clavulanic acid or placebo. The proportion of women who had overall primary outcome events was higher than anticipated (486 [15%] of 3225).…”

A one-stop perineal clinic: our eleven-year experience

“…We advocated the use of short-term prophylactic antibiotics after repair of complex perineal tears but not simple tears. A recently published large multicentre randomized trial found that one prophylactic dose of antibiotic in women undergoing operative vaginal birth significantly reduced the rate of perineal infection [29].…”

Contemporary Issues in Women's Health

“…At present, there are no international guidelines that recommend routine antibiotic prophylaxis for women undergoing OVD as there is insufficient evidence to support the effectiveness of this practice. A recent trial was published from the UK, which investigated the role of antibiotic prophylaxis in preventing maternal infection after OVD . The authors carried out a blinded, randomized controlled trial which took place at 27 obstetric units in the UK.…”