A single dose of antibiotics administered to women following operative vaginal delivery (via forceps or vacuum extraction) was associated with a reduction in infections, a randomized trial found.
A significantly lower portion of women randomized to receive amoxicillin and clavulanic acid had either a confirmed or suspected infection compared with women randomized to placebo (11% vs 19%, RR 0.58, 95% CI 0.49-0.69, P<0.0001), reported Marian Knight, DPhil, of the University of Oxford in England, and colleagues, in The Lancet.
“These findings highlight the urgent need to change current WHO [World Health Organization] antibiotic guidelines and other guidance from [organizations] in the U.K., North America, and Australasia, that do not recommend routine antibiotic prophylaxis for assisted childbirth,” Knight said in a statement.
Knight and colleagues noted that a Cochrane review found that giving antibiotic prophylaxis prior to cesarean section delivery reduces wound infection, endometritis, and serious maternal infection, resulting in the WHO recommending antibiotic prophylaxis prior to C-section delivery. However, no such guidelines exist for antibiotic prophylaxis and vaginal delivery, and evidence on their use is limited.
The Prophylactic Antibiotics in the Prevention of Infection After Operative Vaginal Delivery (ANODE) trial examined patients from 27 obstetric units in the U.K. Eligible participants were ages ≥16 and had undergone operative vaginal delivery at ≥36 weeks gestation. They were randomized to receive either a single dose of intravenous amoxicillin-clavulanic acid, as soon as possible, but no more than 6 hours after giving birth. Women in the placebo group received 20 mL of intravenous sterile 0.9% saline.
The primary outcome was either confirmed or suspected maternal infection within 6 weeks, as defined by a variety of criteria including a new prescription of antibiotics for presumed perineal wound-related infection, endometritis or uterine infection, urinary tract infection with systemic features (pyelonephritis or sepsis), or other systemic infection.
There were 3,420 participants included in the primary intention-to-treat analysis (n=1,715 in the amoxicillin group; n=1,705 in the placebo group). Women were a mean age of about 30, about 85% were white, around three-quarters were primiparous, and about half had induction of labor.
Two-thirds of births were by forceps, and 35% were vacuum extraction, with a large majority of women reporting an episiotomy. Women in the amoxicillin group received the intervention a median of 3.2 hours after birth.
Six weeks after delivery, a lower portion of the intervention group reported a variety of secondary outcomes, including:
- Perineal infection
- Perineal pain
- Use of pain relief for perineal pain
- Need for additional perineal care
Examining safety, three women reported side effects — two in the intervention group with allergic reactions, and one in the placebo group with a rash. There were also two serious adverse events, but they were not judged to be related to the trial intervention, the authors said.
In an accompanying editorial, Vincenzo Berghella, MD, of Thomas Jefferson University in Philadelphia, and Federica Bellussi, MD, of the University of Bologna in Italy, noted a few limitations to the data, namely that the primary outcome was driven by antibiotic prescriptions for presumed perineal infection.
“The criteria used by practitioners to decide to whom to give antibiotics was unclear. Nonetheless, confirmed culture proven sepsis was significantly less in the amoxicillin and clavulanic acid group than in the placebo group,” they wrote.
Knight and colleagues cited data from the study appendix, which found “estimates that for each additional 100 doses of antibiotic used in prophylaxis, 168 treatment doses will be saved, representing a 17% overall reduction in antibiotic use with a policy of universal prophylaxis.”
Study limitations included a follow-up of only 76% for the majority of secondary outcomes. Also, variations in the amount of time to administer antibiotics after delivery meant some doses may have been less effective than if given earlier, the authors said.
Knight and some co-authors disclosed funding from the National Institutes for Health Research (NIHR).
Berghella and Bellussi disclosed no relevant relationships with industry.