Guideline selection and guideline characteristics
A total of 43 guidelines were selected of which 11 were excluded leaving 32 guidelines that fulfilled our inclusion criteria (Figure 1, Table 1). Of the 11 excluded guidelines, 5 were superseded by more up to date guidelines and 6 were not relevant to the review topic (supplementary Table 3).
Risk of bias of included guidelines
None of the selected guidelines fulfilled all 6 quality domains. Three (≈10%) of the guidelines fulfilled 5 of the 6 domains fully while the remaining domain was partially fulfilled and were hence considered high quality guidelines. A total of 18 (56%) of the guidelines fulfilled at least 3 - 4 of the 6 domains, while the remaining 11 (34%) of the guidelines fulfilled 1 - 2 of domains (Figure 2). No guidelines were excluded from the systematic review for failure to fulfill the quality criteria.
Synthesis of results
We analyzed the results under the following clinical categories:
- Asymptomatic bacteriuria:
Two guidelines, produced on behalf of the United States Preventive Task Force (USPTF) [10] and SOGC [11] discussed this topic (Tables 1 & 2). There was concordance between the two guidelines regarding universal screening for asymptomatic bacteriuria in pregnancy using mid-stream urine cultures. Both guidelines recommended treatment for a colony count ≥100000 colony-forming units per milliliter, using an appropriate antibiotic. Both guidelines highlighted the moderate degree of certainty with the regards to the evidence of benefit in support of treatment where the evidence was graded as B-recommendation and II-2A by both guidelines respectively.
- Group B Streptococcal infection (GBS)
Nine guidelines discussed antenatal screening for GBS and / or its intrapartum antibiotic prophylaxis (Tables 1 & 2). These guidelines were produced on behalf of RANZCOG [12], the Canadian Task Force on Preventive Health Care (CTFPHC) [13], SOGC [11], Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC) / Sociedad Española de Medicina Familiar y Comunitaria (SEMFYC) / Sociedad Española de Ginecología y Obstetricia (SEGO) / Sociedad Española de Neonatología (SEN) / Sociedad Española de Quimioterapia (SEQ) [14], New Zealand Medical Association (NZMA) [15], American Academy of Pediatrics (AAP) [16], ACOG [17], RCOG [18] and the World Health Organization (WHO) [19]. There was lack of concordance regarding GBS screening policy between the different guidelines. A policy of routine screening of pregnant women between 35-37 weeks was recommended by CTFPHC, SOGC, SEIMC/ SEMFYC/SEGO/SEN/SEQ, AAP, CDC. In contrast, NZMA and the RCOG did not recommend universal bacteriological screening for GBS. The RCOG concluded that there was lack of clear evidence to show that routine testing for GBS would do “more good than harm”. Although RANZCOG recommended routine screening between 35-37 weeks, they also stated that a risk-based approach was acceptable. Finally, the WHO guideline development group acknowledged the “considerable variations in policies regarding the screening for GBS colonization in pregnant women” and agreed that this recommendation should be implemented in line with local policy.
There was consensus between the different guidelines that the optimal method of screening is a culture-based approach using vaginal or rectal swabs. AAP also suggested that new diagnostic technologies including pigmented enrichment broths, chromogenic agars, DNA probes, and nucleic acid amplification tests might be used. Although there was agreement amongst the guidelines with regards to the use of IV penicillin, there were still some variations in the management protocol. The RCOG guideline recommended an initial dose of benzyl-penicillin of 3g followed by 1.5g 4-hourly till delivery, compared to the NZMA recommendation of a dose of 1.2g and 0.6g for initial and follow-up doses respectively. Ampicillin was also deemed suitable by AAP, ACOG and RANZOG, while the RCOG, AAP and CDC suggested a cephalosporin. In case of penicillin allergy the RCOG and AAP recommended vancomycin and clindamycin respectively.
- Preterm Premature rupture of membranes (P-PROM)
This topic was covered in 5 guidelines, 2 linked guidelines produced on behalf of CNGOF) [20, 21] and one produced by each of SOGC [22], ACOG [23] and the RCOG [24] (Tables 1 & 2). All the guidelines recommended antibiotic prophylaxis if the woman was not in labor. However there were some discrepancies in the gestational age at which antibiotics should be considered. The SOGC guideline recommended that prophylaxis should be given if ≤ 32 weeks’ gestation and considered above 32 weeks if fetal lung maturity could not be proven and/or delivery is not planned (level I-A). CNGOF used a cut off of <37 weeks for using antibiotic prophylaxis (Level A) while ACOG recommended a cut-off of <34+0 weeks of gestation. With regards to antibiotic regimens, the RCOG recommended erythromycin for 10 days, CNGOF suggested amoxicillin, 3rd generation cephalosporins, and erythromycin in monotherapy or erythromycin + amoxicillin (professional consensus) for 7 days (grade C), to be discontinued if vaginal cultures are negative, while ACOG recommended a 7-day course of therapy with a combination of intravenous ampicillin and erythromycin followed by oral amoxicillin and erythromycin. However, the regimen endorsed by SOGC was either ampicillin 2 g IV every 6 hours and erythromycin 250 mg IV every 6 hours for 48 hours followed by amoxicillin 250 mg orally every 8 hours and erythromycin 333 mg orally every 8 hours for 5 days or erythromycin 250 mg orally every 6 hours for 10 days (Level I-A).
Steroids for lung maturity were recommended by both ACOG and RCOG between 24-34 weeks. ACOG and RCOG suggested that it could be considered from 23 weeks and up to 35 weeks respectively. There were some differences in the recommended gestational age for neuro-protection. ACOG recommended <32 weeks compared to the RCOG, which recommended that this would be considered from 24+0 - 29+6. Regarding the place of expectant management, the RCOG and CNGOF stated that outpatient expectant management is possible while ACOG considered this option as not recommended. There were also discrepancies with regards to the management of pregnancies complicated by P-PROM who are GBS positive. The CNGOF and ACOG guidelines suggest that women can have expectant management as long as antibiotics are commenced. Although, the RCOG guideline supported expectant management, it recommended that antibiotics would only be used when in labor or if labor is planned, the guideline also recommended that delivery should be expedited if the gestational age is beyond 34 weeks.
- Intra-amniotic infections / Clinical chorioamnionitis
Three guidelines (ACOG [25], CNGOF [26] & WHO [19]) covered this topic and there was concordance between the guidelines regarding starting combination antibiotic therapy immediately and maintaining it throughout labor (Tables 1 & 2). The guidelines recognized the weakness of evidence to make strong recommendations regarding the duration for which antibiotics should be continued for after delivery. However, there were minor variations in the criteria for diagnosing intra-amniotic infections. According to CNGOF: a body temperature ≥38.0oC with no alternative cause identified and at least 2 of the following signs; fetal tachycardia > 160 bpm for 10 min or longer and uterine pain or purulent cervical discharge (professional consensus). The group also added that the presence of maternal leukocytosis, in the absence of corticosteroids treatment, or increased plasma C-reactive protein should be taken into consideration despite their limited sensitivity and specificity (Evidence Level 3). ACOG used a cut off of ≥39oC for maternal temperature, on its own or 38.0 – 38.9°C together with one additional clinical risk factor. The WHO guideline acknowledged the variability and weakness of evidence regarding diagnostic criteria and did not state a recommendation
Our search identified 3 guidelines for the management of maternal sepsis produced on behalf of the Society for Maternal-Fetal Medicine (SMFM) / ACOG [27], RCOG [28] and the Society of Obstetric Medicine Australia and New Zealand (SOMANZ) [29]. The SMFM/ACOG guideline recommended the use of the quick sequential organ failure assessment (qSOFA) score for patient evaluation, SOMANZ recommended the obstetrically modified qSOFA for initial assessment then the obstetrically modified SOFA for a more thorough assessment. However, the RCOG advised relying on one or more of the following clinical signs suggestive of sepsis: pyrexia, hypothermia, tachycardia, tachypnoea, hypoxia, hypotension, oliguria, impaired consciousness and failure to respond to treatment. Nonetheless, the guideline highlighted that these symptoms might not be present and that they are not necessarily related to the severity. Investigations, fluid and antibiotic management were fairly consistent between the three guidelines (Tables 1 & 2).
We identified a guideline produced on behalf of the British Infection Association [30] specific to the prevention and control of group A streptococcal (GAS) infection in acute healthcare and maternity settings in the UK. This is a detailed guideline addressing practical issues for the care of patients with GAS, their families and healthcare workers involved in their care and recommended antibiotic regimens for this infection.
- Pregnancy-related interventions and procedures
We identified 3 guidelines that addressed issues related to antibiotic prophylaxis in relation to some obstetric-related procedures (Tables 1 & 2). These were produced on behalf of the WHO [19], ACOG [31] and SOGC [32] and covered the following procedures:
Cerclage - Both ACOG and SOGC did not support the use of prophylactic antibiotics to reduce infectious morbidity following elective or emergency cerclage (SOGC - II-3).
Episiotomy - The WHO did not recommend antibiotic prophylaxis for episiotomy.
Cesarean section - There was consistency between the SOGC, ACOG and WHO with regards to antibiotic prophylaxis for cesarean section. Guidelines recommended that a single dose cephalosporin is given 15-60 minutes prior to skin incision, SOGC and ACOG recommended an additional dose of antibiotic prophylaxis if an open abdominal procedure is lengthy (>3 hours) or estimated blood loss is greater than 1500 ml. (SOGC - Grade III-L). Moreover, they advised that in patients with morbid obesity (BMI > 35), doubling the antibiotic dose may be considered (Grade III-B). Although ACOG did not recommend routine screening of pregnant women for methicillin-resistant staphylococcus aureus (MRSA), the guideline suggested that consideration might be given to adding a single dose of vancomycin to the recommended antibiotic prophylaxis regimen for women undergoing caesarean delivery and known to have MRSA.
Operative vaginal delivery - The SOGC guideline concluded that the available evidence did not support the use of prophylactic antibiotics to reduce infectious morbidity following operative vaginal delivery (Grade II-1). The WHO made a similar recommendation (conditional recommendation based on very low-quality evidence).
Obstetric anal sphincter injuries (OASIs) - The WHO recommended routine antibiotic prophylaxis for women who sustain OASIs. ACOG considered a single dose of antibiotic at the time of repair is reasonable (Level B). The SOGC guideline stated, “Prophylactic antibiotics may be considered for the reduction of infectious morbidity associated with repair of third and fourth degree perineal injury” (SOGC - Grade I-B).
Manual removal of the placenta (MROP) - There was some discordance between the guidelines regarding this procedure. ACOG and SOGC highlighted that there were not enough data to argue for or against antibiotic prophylaxis at the time of MROP (SOGC – Grade III). While, routine antibiotic prophylaxis was recommended by the WHO for women undergoing the procedure (strong recommendation based on very low-quality evidence).
Miscellaneous
Our search identified some guidelines that covered different topics. Two of these related to Tetanus, Diphtheria, and Pertussis Vaccination produced on behalf of the Advisory Committee on Immunization Practices (ACIP) [33] and ACOG [34] with concordant advice. The rest of the guidelines [35–41] covered a specific type of bacteria, clinical context or generic advice (Table 1). There was only one guideline identified for each of these topics hence it was not feasible to undertake analysis for concordance.