Different classes of antibiotics given to women routinely for preventing infection at caesarean section
Abstract
Background
Caesarean section increases the risk of postpartum infection for women and prophylactic antibiotics have been shown to reduce the incidence; however, there are adverse effects. It is important to identify the most effective class of antibiotics to use and those with the least adverse effects.
Objectives
To determine, from the best available evidence, the balance of benefits and harms between different classes of antibiotic given prophylactically to women undergoing caesarean section.
Search methods
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2010) and reference lists of retrieved papers.
Selection criteria
We included randomised controlled trials comparing different classes of prophylactic antibiotics given to women undergoing caesarean section. We excluded trials that compared drugs with placebo or drugs within a specific class; these are assessed in other Cochrane Reviews.
Data collection and analysis
Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction.
Main results
We included 29 studies of which 25 provided data on 6367 women. There was a lack of good quality data and important outcomes often included only small numbers of women. This meant we could only conclude that the current evidence shows no overall difference between the different classes of antibiotics in terms of reducing maternal infections after caesarean sections. However, none of the studies looked at outcomes on the baby, nor did they report infections diagnosed after the initial postoperative hospital stay. We were unable to assess what impact, if any, the use of different classes of antibiotics might have on bacterial resistance.
Authors' conclusions
Based on the best currently available evidence, cephalosporins and penicillins have similar efficacy at caesarean section when considering immediate postoperative infections. We have no data for outcomes on the baby, nor on late infections (up to 30 days) in the mother. Clinicians need to consider bacterial resistance and women's individual circumstances.
PICOs
Plain language summary
Comparing different types of antibiotics given routinely to women at caesarean section to prevent infections
Women undergoing caesarean section have an increased likelihood of getting an infection compared with women who give birth vaginally. These infections can be in the surgical incision or in the urine. The infection can also be in the organs within the pelvis, such as the lining of the womb (endometritis). The infections can become serious, causing, for example, an abscess in the pelvis or infection in the blood, and very occasionally can lead to the mother's death. For the prevention of surgical infections, it is generally considered that sound surgical technique is important along with skin antiseptics and the use of antibiotics. However, antibiotics can cause adverse effects such as nausea, vomiting, skin rash and rarely allergic reactions in the mother, and the risk of thrush (candida) for the mother and the baby. Antibiotics, given to women around the time of giving birth, can also change the baby's gut flora which contribute to the baby's developing immune system. Thus antibiotics given at this time may interfere with the baby's developing immune system. This review looked at which types of antibiotics might work best. We found 25 randomised studies, involving 6367 women, which compared cephalosporins with penicillins. Cephalosporins and penicillins had similar effects in reducing infections after caesareans and similar adverse effects. However, none of the included studies assessed infections that arise after the woman is discharged home. The effects were similar whether the caesarean section was an elective or emergency caesarean. None of the studies looked at outcomes on the babies, so it is unclear if one class of antibiotic might be better than another in this respect. Consideration also needs to be given to antibiotics compatible with breastfeeding. Tetracyclines can cause discolouration of teeth in children and are best avoided. We were unable to assess what impact, if any, the use of different types of antibiotics might have on bacterial resistance, and this is a crucial issue when considering which antibiotic might be used.
