Chlorhexidine for prevention of neonatal colonization with group B streptococci. I. In vitro effect of chlorhexidine on group B streptococci

Vaginal chlorhexidine during labour to prevent early-onset neonatal group B streptococcal infection

BACKGROUND

Although early-onset group B β-hemolytic streptococcus (GBS) infection is rare, it accounts for approximately 30% of neonatal infections, has a high mortality rate, and is acquired through vertical transmission from colonized mothers. Several trials have demonstrated the efficacy of intrapartum antibiotic prophylaxis (IAP) for preventing early-onset disease (EOD). Vaginal disinfection with chlorhexidine during labour has been proposed as another strategy for preventing GBS EOD in the preterm and term neonate. Chlorhexidine has been found to have no impact on antibiotic resistance, is inexpensive, and applicable to poorly equipped delivery sites.

OBJECTIVES

To determine the effectiveness of vaginal disinfection with chlorhexidine during labour in women who are colonized with GBS for preventing early-onset GBS infection in preterm and term neonates.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 October 2014) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomized and quasi-randomized trials comparing vaginal disinfection with chlorhexidine (vaginal wash or gel/cream) versus placebo, or no treatment.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed the trials for inclusion and risk of bias, extracted the data and checked them for accuracy.

MAIN RESULTS

We identified no new trials eligible for inclusion in this update. One study was moved from included to excluded studies from the previous version of the review. Four studies, including 1125 preterm and term infants, met the inclusion criteria and reported on at least one of the outcomes of interest. For the comparison chlorhexidine (vaginal wash or gel) versus placebo or no treatment, two studies (n = 987) were pooled. There was no statistically significant difference in early-onset GBS disease (sepsis and/or meningitis) comparing chlorhexidine (vaginal wash or gel/cream) versus placebo or no treatment; risk ratio (RR), 2.32 (95% confidence interval (CI) 0.34 to 15.63); I-squared (I²) = 0% or in GBS pneumonia; RR 0.35 (95% CI 0.01 to 8.6); test for heterogeneity not applicable. The outcome of colonization of the neonate with GBS was reported in three studies (n = 328); RR 0.64 (95% CI 0.40 to 1.01; there was substantial between-study heterogeneity (Chi² = 3.19; P = 0.20; I² = 37%). Maternal mild side effects (stinging or local irritation) (three trials, 1066 women) were more commonly seen in women treated with chlorhexidine (RR 8.50 (95% CI 1.60 to 45.28); there was no heterogeneity (Chi² = 0.01, df = 1 (P = 0.91); I² = 0%). No side effects were reported among the neonates.For the comparison chlorhexidine vaginal wash verus mechanical washing with placebo or no treatment (one study, n = 79), there was a significant reduction in neonatal colonization with GBS; RR 0.32 (95% CI 0.12 to 0.90). Tests for heterogeneity not applicable. There were no other significant results for this comparison.For the comparison chlorhexidine gel or cream versus placebo or no treatment, there were no statistically significant results for the outcomes reported on.The quality of the trials varied and the overall risk of bias was rated as unclear or high. The quality of the evidence using GRADE was very low for the outcomes of the comparison chlorhexidine (vaginal wash or gel/cream) versus placebo or no treatment. These outcomes included: early-onset GBS disease (sepsis and/or meningitis), GBS pneumonia, neonatal colonization with GBS, neonatal mortality due to early-onset GBS infection and adverse (mild) effects in the mother and the neonate.

AUTHORS' CONCLUSIONS

The quality of the four included trials varied as did the risk of bias and the quality of the evidence using GRADE was very low. Vaginal chlorhexidine was not associated with reductions in any of the primary outcomes of early-onset GBS disease (sepsis and/or meningitis) or GBS pneumonia. Vaginal chlorhexidine may reduce GBS colonization of neonates. The intervention was associated with an increased risk of maternal mild adverse effects. The review currently does not support the use of vaginal disinfection with chlorhexidine in labour for preventing early-onset disease. Results should be interpreted with caution as the methodological quality of the studies was poor. As early-onset GBS disease is a rare condition trials with very large sample sizes are needed to assess the effectiveness of vaginal chlorhexidine to reduce its occurrence. In the era of intrapartum antibiotic prophylaxis, such trials may be difficult to justify especially in developed countries.

Chlorhexidine vs. Sterile vaginal wash during labor to prevent neonatal infection

Objective: The purpose of this study was to determine if a dilute solution of chlorhexidine used as a one-time vaginal wash intrapartum can reduce the use of postnatal antibiotics and neonatal infection.

Methods: Term pregnant women in labor were prospectively randomized to receive either 20 cc of 0.4% chlorhexidine (n = 481) or 20 cc of sterile water (n = 466) placebo. Exclusion criteria included fetal distress, clinical infection, cervical dilatation >6 cm, and known allergy to chlorhexidine. Outcome variables included the incidence of neonatal pneumonia, culture proven neonatal sepsis, and use of the antibiotics in the neonate. Continuous variables were compared using the Mann-Whitney U-test and discrete variables were compared with the chi-square test.

Results: The length of ruptured membranes (mean ± S.D.) between the chlorhexidine group (408 ± 589 min) and control group (352 ± 318 min) was not significantly different (P = 0.85, 95% confidence interval 354–462). Fifteen neonates (3.2%) in the chlorhexidine group and 9 (1.9%) in the control group received antibiotics in the postnatal period (P = 0.32, 95% confidence interval 0.72–3.72). There was one case of pneumonia in the control group and no cases of sepsis in either group.

Conclusions: A one-time chlorhexidine vaginal wash does not decrease the use of antibiotics or incidence of neonatal infection in our population.

Safety and impact of chlorhexidine antisepsis interventions for improving neonatal health in developing countries

Affordable, efficacious, and safe interventions to prevent infections and improve neonatal survival in low-resource settings are needed. Chlorhexidine is a broad-spectrum antiseptic that has been used extensively for many decades in hospital and other clinical settings. It has also been given as maternal vaginal lavage, full-body newborn skin cleansing, and/or umbilical cord cleansing to prevent infection in neonates. Recent evidence suggests that these chlorhexidine interventions may have significant public health impact on the burden of neonatal infection and mortality in developing countries. This review examines the available data from randomized and nonrandomized studies of chlorhexidine cleansing, with a primary focus on potential uses in low-resource settings. Safety issues related to chlorhexidine use in newborns are reviewed, and future research priorities for chlorhexidine interventions for neonatal health in developing countries are discussed. We conclude that maternal vaginal cleansing combined with newborn skin cleansing could reduce neonatal infections and mortality in hospitals of sub-Saharan Africa, but the individual impact of these interventions must be determined, particularly in community settings. There is evidence for a protective benefit of newborn skin and umbilical cord cleansing with chlorhexidine in the community in south Asia. Effectiveness trials in that region are required to address the feasibility of community-based delivery methods such as incorporating these interventions into clean birth kits or training programs for minimally skilled delivery assistants or family members. Efficacy trials for all chlorhexidine interventions are needed in low-resource settings in Africa, and the benefit of maternal vaginal cleansing beyond that provided by newborn skin cleansing needs to be determined.

Use of Vaginally Administered Chlorhexidine During Labor to Improve Pregnancy Outcomes

OBJECTIVE

Our objective was to determine the potential for chlorhexidine used as a vaginal and neonatal wash to reduce adverse outcomes of pregnancy, especially in developing countries.

DATA SOURCES

We searched the English literature from January 1950 through October 2005 for all articles related to the use of chlorhexidine.

METHODS OF STUDY SELECTION

Every article on chlorhexidine use in pregnancy and in the newborn period was reviewed in detail. The results of every study in which chlorhexidine was used as a vaginal treatment, with or without a neonatal wash, for all pregnancy outcomes except mother-to-child transmission of human immunodeficiency virus, are summarized in this review.

TABULATION, INTEGRATION AND RESULTS

Chlorhexidine is a highly effective killer of most bacteria, has an excellent safety profile, rarely is associated with bacterial resistance, is easy to administer, and costs a few cents per application. When used as a vaginal or newborn disinfectant, it clearly reduces bacterial load, including transmission of Group B Streptococcus from the mother to the fetus. Nevertheless, in developed countries, chlorhexidine generally has not been shown to significantly reduce life-threatening maternal or neonatal infections. However, 2 large but not randomized studies, one in Malawi and the other in Egypt, suggest that important reductions in maternal and neonatal sepsis and neonatal mortality may be achievable with vaginal or neonatal chlorhexidine treatment.

CONCLUSION

With 4 million neonates and about 700,000 pregnant or recently pregnant women-mostly in developing countries-dying each year, many from infections originating in the vagina, further study of this highly promising treatment is indicated.

Vaginal chlorhexidine during labour to prevent early-onset neonatal group B streptococcal infection

BACKGROUND

Early-onset group B beta-hemolytic streptococcus (GBS) infection accounts for approximately 30% of neonatal infections, has a high mortality rate and is acquired through vertical transmission from colonized mothers. Several trials have demonstrated the efficacy of intrapartum chemoprophylaxis (IPC) for preventing early-onset disease (EOD). Vaginal disinfection with chlorhexidine during labour has been proposed as another strategy for preventing GBS EOD in the preterm and term neonate. Chlorhexidine has been found to have no impact on antibiotic resistance, is inexpensive, and applicable to poorly equipped delivery sites.

OBJECTIVES

To determine the effectiveness of vaginal disinfection with chlorhexidine during labour for preventing early-onset GBS infection in preterm and term neonates.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth trials register (October 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2003), MEDLINE (1966 to October 2003), EMBASE (1980 to March 2003), CINAHL (1982 to March 2003) and LILACS (1982 to September 2003).

SELECTION CRITERIA

Randomized and quasi-randomized trials comparing vaginal disinfection with chlorhexidine to placebo, or no treatment.

DATA COLLECTION AND ANALYSIS

We extracted information from the results sections of the included studies. We reported relative risk (RR) and risk difference (RD) with 95% confidence intervals (CI) for dichotomous outcomes. We calculated the number needed to treat (NNT) with 95% CIs when a statistically significant RD was found. We used a chi square test (chi2) and the I2 analysis to test for heterogeneity, and applied a fixed or random effects model accordingly.

MAIN RESULTS

Five studies, including approximately 2190 term and preterm infants, met the inclusion criteria and reported on at least one of the outcomes of interest for this systematic review. When all studies were combined there was a statistically significant (p = 0.005) reduction in colonisation (RR 0.72, 95% CI 0.56 to 0.91); RD -0.16 (95% CI -0.26 to -0.05); NNT 6 (95% CI 4 to 20). There was no statistically significant between-study heterogeneity. There was no statistically significant between-study heterogeneity both for RR (chi(2) = 3.21 [p = 0.2], I(2) = 37.8%) and for RD (chi(2) = 1.66 [p = 0.44], I(2) = 0%). There was no statistically significant reduction in EOD including GBS infection, GBS pneumonia, GBS meningitis or mortality.

REVIEWERS' CONCLUSIONS

Vaginal chlorhexidine resulted in a statistically significant reduction in GBS colonisation of neonates, but was not associated with reductions in other outcomes. The review currently does not support the use of vaginal disinfection with chlorhexidine in labour for preventing EOD. Results should be interpreted with caution as the methodological quality of the studies was poor.

Effect of chlorhexidine on genital microflora, Neisseria gonorrhoeae, and Trichomonas vaginalis in vitro

BACKGROUND

Chlorhexidine is a disinfectant that has been used in skin and mouth washes and as a preservative in some vaginal lubricants. A gel containing 0.25% chlorhexidine gluconate has been found to be effective against Chlamydia trachomatis in vitro and in animal models. Applied vaginally, 5 g of this gel could achieve vaginal fluid concentrations of < or = 1250 microg/ml.

GOAL

To test the in vitro activity of chlorhexidine in a gel over a pH range of 4 to 8 in the presence or absence of blood.

STUDY DESIGN

Organisms were exposed to chlorhexidine for 30 minutes to 2 hours, and the minimum cidal concentration (MCC) was calculated.

RESULTS

The MCC for Neisseria gonorrhoeae was 25 microg/ml at 30 minutes and 12.5 microg/ml at 1 to 2 hours of exposure, whereas the MCC for Trichomonas vaginalis was 1250 microg/ml. Chlorhexidine was more active at pH 8 than pH 4, and less active in the presence of blood. The MCC for Lactobacillus crispatus was 1250 microg/ml at pH 4 and only 125 microg/ml at pH 8.

CONCLUSIONS

Based on its in vitro activity, chlorhexidine may be an appropriate topical microbicide for prevention of gonorrhea, but not for prevention of trichomoniasis. This study suggests that the presence of blood and pH affect the activity of chlorhexidine against genital pathogens and commensals.

Chlorhexidine versus sterile water vaginal wash during labor to prevent peripartum infection

OBJECTIVE

Our purpose was to determine whether a dilute solution of chlorhexidine used as a one-time vaginal wash intrapartum can reduce the incidence of intraamniotic infection or endometritis in laboring pregnant women.

STUDY DESIGN

Term pregnant women in labor were prospectively randomized to receive either 20 ml of 0.4% chlorhexidine (n = 481) or 20 ml of sterile water (n = 466) placebo. All patients were monitored for risk factors associated with intraamniotic infection. Continuous variables were compared with the Mann-Whitney U test and discrete variables were compared with Fisher's exact test.

RESULTS

No significant differences in infection were found between the chlorhexidine and placebo groups. During the study period 21 of 466 women (4.5%) had intraamniotic infection in the control group compared with 25 of 481 women (5.2%) receiving chlorhexidine (p = 0.65, 95% confidence interval 0.82 to 1.41). Nine women in the placebo group (1.9%) and 9 women in the chlorhexidine group (1.9%) had endometritis (p = 1.0, 95% confidence interval 0.62 to 1.56).

CONCLUSIONS

Our findings suggest that a one-time 0.4% chlorhexidine vaginal wash does not decrease the incidence of infectious morbidity in parturients, compared with the use of sterile water.

Randomized study of vaginal chlorhexidine disinfection during labor to prevent vertical transmission of group B streptococci

OBJECTIVE

To evaluate the effect of vaginal disinfection with chlorhexidine gel during labor on vertical transmission of group B streptococcus, as a method to prevent vertical transmission and subsequent neonatal early onset group B streptococcal disease.

STUDY DESIGN

A prospective study with randomization of 1020 parturients to one of three groups as soon as labor started. In all parturients, anus, introitus and cervix were cultured semiquantitatively. Two groups were treated double-blindly with 10 ml of either a 0.3% chlorhexidine gel or a placebo gel, applicated around the portio and into the fornices. If labor still continued, a second application was given after 10 h. The third group received no treatment. Ear, pharynx and umbilicus of all newborns were also cultured semiquantitatively.

RESULTS

Nine hundred and eighty one women were evaluated. The overall incidence of group B streptococcal carriership was 19.4%. Vertical transmission was 52.4% in the chlorhexidine group, 71.4% in the placebo group and 66.7% in the control group (P = 0.069). When testing the transmission rates for the chlorhexidine versus the combined placebo plus control group (69.3%), the difference was 16.9% (P = 0.026).

CONCLUSION

Vaginal disinfection with a chlorhexidine gel during labor modestly reduces group B streptococcal vertical transmission. Because the method is cheap, simple and safe, it should be considered for routine use. Our results indicate that it may reduce the incidence of early onset group B streptococcal sepsis by 2-32%.

Prevention of excess neonatal morbidity associated with group B streptococci by vaginal chlorhexidine disinfection during labour. The Swedish Chlorhexidine Study Group

Streptococcus agalactiae transmitted to infants from the vagina during birth is an important cause of invasive neonatal infection. We have done a prospective, randomised, double-blind, placebo-controlled, multi-centre study of chlorhexidine prophylaxis to prevent neonatal disease due to vaginal transmission of S agalactiae. On arrival in the delivery room, swabs were taken for culture from the vaginas of 4483 women who were expecting a full-term single birth. Vaginal flushing was then done with either 60 ml chlorhexidine diacetate (2 g/l) (2238 women) or saline placebo (2245) and this procedure was repeated every 6 h until delivery. The rate of admission of babies to special-care neonatal units within 48 h of delivery was the primary end point. For babies born to placebo-treated women, maternal carriage of S agalactiae was associated with a significant increase in the rate of admission compared with non-colonised mothers (5.4 vs 2.4%; RR 2.31, 95% CI 1.39-3.86; p = 0.002). Chlorhexidine reduced the admission rate for infants born of carrier mothers to 2.8% (RR 1.95, 95% CI 0.94-4.03), and for infants born to all mothers to 2.0% (RR 1.48, 95% CI 1.01-2.16; p = 0.04). Maternal S agalactiae colonisation is associated with excess early neonatal morbidity, apparently related to aspiration of the organism, that can be reduced with chlorhexidine disinfection of the vagina during labour.

Chlorhexidine for prevention of neonatal colonization with group B streptococci. V. Chlorhexidine concentrations in blood following vaginal washing during delivery

Chlorhexidine 2 g/l was applied to the vagina of 96 women during delivery, whereas 28 served as controls. Both groups were given a shower using a chlorhexidine soap, and outer washing of the outer anogenital tract was also performed in all patients using chlorhexidine 2 g/l. Using a gas chromatographic method with a detection limit of 10 ng chlorhexidine per ml blood, 10-83 ng/ml was demonstrated in 34 (35%) of the study group patients, whereas the remaining study group patients and controls showed no detectable chlorhexidine. Performing the washing a second time after 6 hours in 14 patients and a third time in 3 patients after a further 6 hours did not result in increased serum levels. It was concluded that small amounts of chlorhexidine are absorbed through the vaginal mucosa and that chlorhexidine is not accumulated in the blood on repeated usage with 6 hour intervals during delivery.

Prevention of group B streptococci transmission during delivery by vaginal application of chlorhexidine gel

In a prospective study in 227 parturients, carriership of group B streptococci was established to be 25%. In carriers, transmission of streptococci to the newborn occurred in 50%. 10 ml of a chlorhexidine gel containing hydroxypropylmethylcellulose was introduced into the vagina during labor in 17 parturients, who were known to be carriers of group B streptococci from the first trimester of pregnancy. In none of the newborns from these mothers colonization by group B streptococci did occur. Vaginal application of chlorhexidine may prevent transmission of group B streptococci, and serve as an alternative to intrapartum prophylaxis using antibiotics. A large multicenter randomized controlled study should be performed to confirm this hypothesis.

A comparative study of the microbial antiadherence capacities of three antimicrobial agents

The antimicrobioal agents, taurolidine, chlorhexidine and povidone-iodine were examined for microbial anti-adherence activity. Two adherence systems were investigated using light microscopic and radio-isotopic assay methods: that of an oral isolate of Candida albicans to human buccal epithelial cells and of a urine isolate of Escherichia coli to human uroepithelial cells. Each of the three agents exhibited significant anti-adherence activity which was concentration dependent. The activity was expressed at subminimum inhibitory concentrations of the agents. Treatment of either the microbial or epithelial cells resulted in significant reductions in adhering micro-organisms. Consideration of the data in respect of the skewness coefficient and percentage clear epithelial cells indicated that the agents exhibited a broadly based anti-adherence capacity.

Chlorhexidine for prevention of neonatal colonization with group B streptococci. IV. Depressed puerperal carriage following vaginal washing with chlorhexidine during labour

The effect of vaginal washing with chlorhexidine acetate, 2 g/l at delivery, on the colonization of the urogenital tract with group B streptococci (GBS) 4 days later was investigated. Patients who were culture-positive for GBS in urethra and/or cervix in pregnancy weeks 32 and 36 as well as at delivery were included in a prospective study. The washing procedure was performed in 31 parturients, and 10 (32%) were culture-negative at day 4 after delivery. In contrast, only 7/47 (15%) non-washed controls were negative at day 4 (p = 0.044). The results demonstrate a prolonged suppressive effect of vaginal washing with chlorhexidine on the recovery of GBS from the urogenital tract in this highly selected patient group.

Chlorhexidine for prevention of neonatal colonization with group B streptococci. III. Effect of vaginal washing with chlorhexidine before rupture of the membranes

A single vaginal washing with 2 g/l of chlorhexidine was performed before rupture of the membranes in 19 parturients who were urogenital carriers of group B streptococci (GBS). Two (11%) of the infants became colonized immediately after birth, in contrast to 16 of 41 (39%) infants to controls (P = 0.02). A significant reduction of GBS colonization of the ear (P = 0.02) and umbilicus (P = 0.01) was noted. Taken together, 2 of 57 (4%) cultures obtained at birth were positive in the chlorhexidine group, in contrast to 30 of 123 (24%) among the controls (P less than 0.01). These findings raise hope for the design of a simple washing procedure which might prevent serious infections in the early neonatal period with GBS but also with other chlorhexidine-sensitive organisms.

Reduced colonization of newborns with group B streptococci following washing of the birth canal with chlorhexidine

Possible measures for prevention of neonatal group B streptococcal (GBS) septicemia include active or passiv immunoprophylaxis and administration of penicillin to mothers and infants. In a previous study we have found GBS to be extremely sensitive to chlorhexidine. Furthermore vaginal washing with chlorhexidine diminished the recovery of GBS from parturients. In order to study the effect of chlorhexidine washing upon the colonization of newborns, a study group of chronic GBS carriers, i.e. women who were GBS positive in the 32-36 gestational week as well as during labor was selected. In 18 of these females chlorhexidine washing was performed prior to delivery while 33 chronic carriers served as controls. Screening during labor was performed in 945 consecutive patients. Cultures were collected from the external ear, throat and umbilicus of all infants within 5 minutes of birth and at day 4 of life. At birth 22% of the infants of the chlorhexidine washed mothers were colonized with GBS, in contrast to 52% of the infants from the chronic GBS carriers (p less than 0.05). The proportion of infants harboring GBS at day 4 were similar in the two groups (Tab. I). Among the 945 consecutively screened women, 164 harbored GBS and 54 (33%) of their 164 infants were colonized at birth. The colonization rate of the infants from chronic GBS carriers was significantly higher, 17 of 33 infants (p less than 0.05). This may reflect that the risk of contracting GBS by infants increases with the quantity of GBS in the birth channel.(ABSTRACT TRUNCATED AT 250 WORDS)

Chlorhexidine for prevention of neonatal colonization with group B streptococci. II. Chlorhexidine concentrations and recovery of group B streptococci following vaginal washing in pregnant women

The effect of a single washing of the urogenital tract with 0.5 g/l chlorhexidine was studied in 6 women in weeks 38-40 of pregnancy, among whom 5 were carriers of group B streptococci in urethra and/or cervix. The chlorhexidine concentrations varied between 25 and 200 mg/l during the first hour after washing in 5 of the 6 women, whereas one patient showed concentrations below 25 mg/l. With the exception of one patient, all individuals showed concentrations less than 25 mg/l at 3-24 h after washing. A clear suppression of the number of colony-forming units of GBS was already apparent after 60 min and was still evident 6 h after chlorhexidine washing.