In addition to these evidence-based recommendations, the guideline development group also identifies points of best clinical practice in the original guideline document.
Levels of evidence (Ia-IV) and grading of recommendations (A-C) are defined at the end of the "Major Recommendations" field.
Antenatal Screening
C - Routine screening (either bacteriological or risk based) for antenatal group B streptococcal (GBS) carriage is not recommended.
Prophylaxis
Should Women Be Treated Antenatally, if GBS is Detected Incidentally?
B - Antenatal treatment with penicillin is not recommended.
Should Women Receive Intrapartum Antibiotic Prophylaxis, if GBS Detected Incidentally?
C - Intrapartum antibiotic prophylaxis should be considered if GBS is detected incidentally.
Should Women Receive Intrapartum Antibiotic Prophylaxis if GBS Was Detected in a Previous Pregnancy?
C - There is no good evidence to support the administration of intrapartum antibiotic prophylaxis to women in whom GBS carriage was detected in a previous pregnancy. [Evidence level IV]
Should Women with a Previous Baby with Neonatal GBS Disease Be Offered Intrapartum Antibiotic Prophylaxis?
C - Intrapartum antibiotic prophylaxis should be offered to women with a previous baby with neonatal GBS disease.
Vaginal or rectal swabs are not helpful, as intrapartum antibiotic prophylaxis would be recommended even if these swabs were negative for GBS. [Evidence level IV]
Intrapartum Antibiotic Prophylaxis for Other Groups
C - Clinicians should use Table 1 in the original guideline document to inform discussions with women regarding the use of intrapartum antibiotic prophylaxis in the presence of known risk factors including incidental carriage. The argument for prophylaxis becomes stronger in the presence of two or more risk factors. [Evidence level IV]
A - If chorioamnionitis is suspected, broad-spectrum antibiotic therapy including an agent active against GBS should replace GBS-specific antibiotic prophylaxis. [Evidence level Ib]
B - Intrapartum antibiotic prophylaxis (IAP) should be offered to women with GBS bacteriuria in the current pregnancy after discussion.
GBS bacteriuria is associated with a higher risk of neonatal disease. Again, it is not possible to quantify this increased risk. These women should be offered antibiotic prophylaxis after appropriate discussion. Women with GBS urinary tract infection during pregnancy should receive appropriate treatment at the time of diagnosis as well as antibiotic prophylaxis. [Evidence level III]
C - Antibiotic prophylaxis is not required for women undergoing planned caesarean section in the absence of labour and with intact membranes.
Women undergoing planned caesarean delivery in the absence of labour or membrane rupture do not require antibiotic prophylaxis for GBS, regardless of GBS colonisation status. The risk of neonatal GBS disease is extremely low in this circumstance. [Evidence level IV]
C - Antibiotic prophylaxis for GBS is unnecessary for women with preterm rupture of membranes unless they are in established labour.
Antibiotic administration specifically for GBS colonisation is not necessary prior to labour. If these women are known to be colonised with GBS, antibiotic prophylaxis should be considered, especially if labour occurs prior to 37 weeks (see Table 1 in original guideline document). [Evidence level IV]
Which Antibiotics Should be Given?
B - Penicillin should be administered as soon as possible after the onset of labour. Clindamycin should be administered to those women allergic to penicillin.
It is recommended that intravenous penicillin 3 g be given as soon as possible after the onset of labour and 1.5 g four-hourly until delivery. Clindamycin 900 mg should be given intravenously eight-hourly to those allergic to penicillin. It should be noted that these doses are based on tradition rather than good evidence. Broad-spectrum antibiotics such as ampicillin should be avoided if possible, as concerns have been raised regarding increased rates of neonatal Gram negative sepsis. To optimise the efficacy of antibiotic prophylaxis, the first dose should be given at least two hours prior to delivery. [Evidence level III]
Management of the Newborn Infant
Sick Infants
C - Newborn infants with clinical signs of early-onset GBS disease should be treated promptly with the necessary antibiotics.
Whether they received intrapartum antibiotics or not, any newborn infant with clinical signs compatible with infection should be treated promptly with broad-spectrum antibiotics, which provide cover against early-onset GBS disease and other common pathogens. Blood cultures should always be obtained before antibiotic treatment is commenced, and cerebrospinal fluid (CSF) cultures should be considered. [Evidence level IV]
Low-Risk Term Infants
B - Postnatal antibiotic prophylaxis is not recommended for low-risk term infants.
Well Infant with Risk Factor, Including Incidental Finding of Maternal GBS Carriage, With or Without Intrapartum Antibiotics
C - Randomised controlled trials (RCTs) have not provided a sufficient evidence base for clear treatment recommendations in well newborn infants.
Previous Infant with GBS Disease
C - For an infant whose mother had a previous infant with GBS disease, either clinical evaluation after birth and observation for at least twelve hours are necessary, or blood cultures should be obtained and the infant treated with penicillin until the culture results are available.
Breastfeeding
C - Breastfeeding does not increase the risk of neonatal GBS disease, and women concerned about late-onset disease should be given the usual advice about breastfeeding. [Evidence level IV]
Definitions:
Grading of Recommendations
Grade A - Requires at least one randomised controlled trial as part of a body of literature of overall good quality and consistency addressing the specific recommendation (evidence levels Ia, Ib)
Grade B - Requires the availability of well-conducted clinical studies but no randomised clinical trials on the topic of recommendations (evidence levels IIa, IIb, III)
Grade C - Requires evidence obtained from expert committee reports or opinions and/or clinical experience of respected authorities. Indicates an absence of directly applicable clinical studies of good quality (evidence level IV)
Levels of Evidence
Ia: Evidence obtained from meta-analysis of randomised controlled trials
Ib: Evidence obtained from at least one randomised controlled trial
IIa: Evidence obtained from at least one well-designed controlled study without randomisation
IIb: Evidence obtained from at least one other type of well-designed quasi-experimental study
III: Evidence obtained from well-designed non-experimental descriptive studies, such as comparative studies, correlation studies, and case studies
IV: Evidence obtained from expert committee reports or opinions and/or clinical experience of respected authorities
