From the Guidelines
Pregnant women with vaginal Streptococcus agalactiae (Group B Streptococcus, GBS) colonization should receive intravenous antibiotic prophylaxis during labor to prevent transmission to the newborn. The recommended management for these women includes:
- Universal screening at 35-37 weeks gestation with vaginal-rectal swabs to identify women who need intrapartum prophylaxis 1
- Intrapartum chemoprophylaxis for women identified as GBS carriers, with penicillin G as the first-line agent, administered as a 5 million unit IV loading dose, followed by 2.5-3 million units every 4 hours until delivery 1
- Alternative regimens for women with penicillin allergy, including cefazolin, clindamycin, or vancomycin, depending on the risk of anaphylaxis and susceptibility testing results 1
- Antibiotic prophylaxis should begin when labor starts or membranes rupture, ideally at least 4 hours before delivery for maximum effectiveness 1
- Women with GBS bacteriuria in any concentration during their current pregnancy or who previously gave birth to an infant with GBS disease should receive intrapartum antimicrobial prophylaxis 1
- Women with negative vaginal and rectal GBS screening cultures within 5 weeks of delivery do not require intrapartum antimicrobial prophylaxis for GBS, even if obstetric risk factors develop 1
Key considerations in the management of GBS colonization in pregnancy include:
- The risk of transmission to the newborn and the potential for serious neonatal infections, including sepsis, pneumonia, and meningitis 1
- The importance of universal screening and intrapartum prophylaxis in reducing the risk of early-onset GBS disease in newborns 1
- The need for individualized management based on the woman's medical history, allergy status, and susceptibility testing results 1
From the Research
Recommended Management for Pregnant Women with Vaginal Streptococcus (Group B Streptococcus, GBS) Colonization
The recommended management for pregnant women with vaginal Streptococcus (Group B Streptococcus, GBS) colonization involves several key steps:
- Screening for GBS colonization between 36 0/7 to 37 6/7 weeks of gestation 2
- Intrapartum antibiotic prophylaxis (IAP) for women who test positive for GBS colonization 3, 4, 2
- Administration of penicillin, ampicillin, or cefazolin as the recommended antibiotics for prophylaxis, with clindamycin and vancomycin reserved for cases of significant maternal penicillin allergy 2
- Skin testing for pregnant women with a history of penicillin allergy to confirm or delabel the allergy 2
Risk Assessment and Empiric Antibiotics
- Separate consideration should be given to infants born at less than 35 weeks' and more than or equal to 35 weeks' gestation when performing GBS risk assessment 2
- Empiric antibiotics are recommended for infants at high risk for GBS early-onset disease 2
Prevention of GBS Disease
- Intrapartum antibiotic prophylaxis is effective in preventing GBS early-onset disease, but currently, there is no approach for the prevention of GBS late-onset disease 2
- The risk-benefit balance of screening and antibiotic prophylaxis should be considered, taking into account the potential risks of anaphylactic reactions and the benefits of preventing GBS disease 4
Diagnosis and Prophylaxis
- Anal and vaginal GBS culture can be used as part of differentiated obstetrical care to reduce early neonatal infection 5
- The rates, risk factors, and incidence of neonatal disease may vary in different communities and need to be thoroughly evaluated to allow the most appropriate preventive strategy to be selected 5