Vaginal cleansing with antiseptic solution before cesarean delivery to reduce infections after surgery

We set out to determine from randomized controlled trials if cleansing the vagina with an antiseptic solution before a cesarean delivery safely decreases the risk of maternal infections.

What is the issue?

Cleansing the vagina before the cesarean delivery can reduce the number of bacteria that are naturally present in the vagina. These bacteria in the vagina and cervix can move up into the uterus during the surgical procedure and cause infection in the lining of the uterus and in the surgical wound. Antibiotics are routinely given before the surgery to reduce the risk of infections, but some women still suffer from these complications. Some antibiotics do not always eradicate all bacteria, and antibiotic resistant bacteria may be present. Vaginal preparation may not be included in the care provided to women to reduce infection following surgery. Vaginal cleansing solutions, such as chlorhexidine and povidone-iodine are inexpensive, and have very few side effects.

Why is this important?

Cesarean deliveries are common, with almost one in three babies born by cesarean in some countries such as the USA. It is not uncommon for women having a cesarean delivery to develop an infection of the uterus (endometritis) or a problem with their skin incision. The risk of infection is greater if a woman’s waters have broken or she is in labor before the cesarean section. These complications may slow a woman’s recovery from the surgery and can affect her ability to take care of her baby. This is a Cochrane Review first published in 2010 and updated in 2012, 2014, and in 2017.

What evidence did we find?

We searched for new evidence on 7 July 2019. In this update, we have included 21 randomized controlled studies, involving a total of 7038 women undergoing cesarean section. The studies took place in 10 countries (Saudi Arabia, Pakistan, Iran, Thailand, Turkey, USA, Egypt, UK, Kenya and India). The control group had no vaginal preparation in 18 studies and in three studies participants used a saline vaginal preparation. We did not include trials that did not give antibiotics before or during the surgery, or where women received vaginal preparation during labor. Seventeen studies used povidone-iodine for vaginal cleansing, three chlorhexidine, and one benzalkonium chloride.

Cleansing the vagina with antiseptic solution immediately before cesarean delivery probably reduces the incidence of post-cesarean infection of the uterus (20 trials, 6918 women; moderate-certainty evidence). This reduction was seen for both iodine-based solutions and chlorhexidine-based solutions. The risk of postoperative fever (16 trials, 6163 women) and postoperative wound infection (18 trials, 6385 women) are also probably reduced by vaginal cleansing; both moderate-certainty evidence). The risk of having wound complication or infection of the uterus may be lower in women receiving preoperative vaginal cleansing with antiseptic solution (2 trials, 499 women). None of the studies reported any adverse events, such as an allergic reaction to the cleansing solution or irritation.

Further analysis suggested a greater effect for those women in labour versus those not in labour for four out of five outcomes examined (post-cesarean infection of the uterus; postoperative fever; postoperative wound infection; wound complication or infection of the uterus) but this apparent difference needs to be investigated further in future trials. We did not observe any differences between groups of women with ruptured membranes and women with intact membranes.

What does this mean?

Cleansing the vagina with povidone-iodine or chlorhexidine solution (compared to saline or not cleansing) immediately before cesarean delivery probably reduces the risk of infection of the uterus, fever, and infection of the surgical wound. Further analysis found that these benefits were typically present whether iodine-based or chlorhexidine-based solutions were used and when women were in labor before the cesarean.

Vaginal preparation is a simple and well-tolerated way to lower the chances of developing an infection after having a baby by cesarean.

Authors' conclusions: 

Vaginal preparation with povidone-iodine or chlorhexidine solution compared to saline or not cleansing immediately before cesarean delivery probably reduces the risk of post-cesarean endometritis, postoperative fever, and postoperative wound infection. Subgroup analysis found that these benefits were typically present whether iodine-based or chlorhexidine-based solutions were used and when women were in labor before the cesarean. The suggested benefit in women in labor needs further investigation in future trials.

There was moderate-certainty evidence using GRADE for all reported outcomes, with downgrading decisions based on limitations in study design or imprecision.

As a simple intervention, providers may consider implementing preoperative vaginal cleansing with povidone-iodine or chlorhexidine before performing cesarean deliveries. Future research on this intervention being incorporated into bundles of care plans for women receiving cesarean delivery will be needed.

Read the full abstract...
Background: 

Cesarean delivery is one of the most common surgical procedures performed by obstetricians. Infectious morbidity after cesarean delivery can have a tremendous impact on the postpartum woman's return to normal function and her ability to care for her baby. Despite the widespread use of prophylactic antibiotics, postoperative infectious morbidity still complicates cesarean deliveries. This is an update of a Cochrane Review first published in 2010 and subsequently updated in 2012, twice in 2014, in 2017 and 2018.

Objectives: 

To determine if cleansing the vagina with an antiseptic solution before a cesarean delivery decreases the risk of maternal infectious morbidities, including endometritis and wound complications. We also assessed the side effects of vaginal cleansing solutions to determine adverse events associated with the intervention.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth’s Trials Register, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (7 July 2019), and reference lists of retrieved studies.

Selection criteria: 

We included randomized controlled trials (RCTs) and quasi-RCTs assessing the impact of vaginal cleansing immediately before cesarean delivery with any type of antiseptic solution versus a placebo solution/standard of care on post-cesarean infectious morbidity.

Cluster-RCTs were eligible for inclusion, but we did not identify any. We excluded trials that utilized vaginal preparation during labor or that did not use antibiotic surgical prophylaxis. We also excluded any trials using a cross-over design. We included trials published in abstract form only if sufficient information was present in the abstract on methods and outcomes to analyze.

Data collection and analysis: 

At least three of the review authors independently assessed eligibility of the studies. Two review authors were assigned to extract study characteristics, quality assessments, and data from eligible studies.

Main results: 

We included 21 trials, reporting results for 7038 women evaluating the effects of vaginal cleansing (17 using povidone-iodine, 3 chlorhexidine, 1 benzalkonium chloride) on post-cesarean infectious morbidity. Trials used vaginal preparations administered by sponge sticks, douches, or soaked gauze wipes. The control groups were typically no vaginal preparation (17 trials) or the use of a saline vaginal preparation (4 trials). One trial did not report on any outcomes of interest. Trials were performed in 10 different countries (Saudi Arabia, Pakistan, Iran, Thailand, Turkey, USA, Egypt, UK, Kenya and India). The overall risk of bias was low for areas of attrition, reporting, and other bias. About half of the trials had low risk of selection bias, with most of the remainder rated as unclear. Due to lack of blinding, we rated performance bias as high risk in nearly one-third of the trials, low risk in one-third, and unclear in one-third.

Vaginal preparation with antiseptic solution immediately before cesarean delivery probably reduces the incidence of post-cesarean endometritis from 7.1% in control groups to 3.1% in vaginal cleansing groups (average risk ratio (aRR) 0.41, 95% confidence interval (CI) 0.29 to 0.58; 20 trials, 6918 women; moderate-certainty evidence). This reduction in endometritis was seen for both iodine-based solutions and chlorhexidine-based solutions. Risks of postoperative fever and postoperative wound infection are also probably reduced by vaginal antiseptic preparation (fever: aRR 0.64, 0.50 to 0.82; 16 trials, 6163 women; and wound infection: RR 0.62, 95% CI 0.50 to 0.77; 18 trials, 6385 women; both moderate-certainty evidence). Two trials found that there may be a lower risk of a composite outcome of wound complication or endometritis in women receiving preoperative vaginal preparation (RR 0.46, 95% CI 0.26 to 0.82; 2 trials, 499 women; low-certainty evidence). No adverse effects were reported with either the povidone-iodine or chlorhexidine vaginal cleansing.

Subgroup analysis suggested a greater effect with vaginal preparations for those women in labour versus those not in labour for four out of five outcomes examined (post-cesarean endometritis; postoperative fever; postoperative wound infection; composite wound complication or endometritis). This apparent difference needs to be investigated further in future trials. We did not observe any subgroup differences between women with ruptured membranes and women with intact membranes.