The Centers for Disease Control and Prevention (CDC) have recently published new guidelines for prevention of group B streptococcal (GBS) disease. 1 Prevention of prenatal group B streptococcal diseaseA public health perspective. MMWR. 1996; 45 (RR-7): 1-24 Google Scholar These new guidelines are in consensus with the American Academy of Pediatrics (AAP) and the American College of Obstetricians and Gynecologists (ACOG), who previously published their own, different, recommendations. 2 American Academy of PediatricsGuidelines for prevention of group B streptococcal (GBS) infection by chemoprophylaxis. Committee on infectious diseases and committee on fetus and newborn. Pediatrics. 1992; 90: 775-778 PubMed Google Scholar , 3 Group B streptococcal infections in pregnancyACOG's recommendations. ACOG Newsl. 1993; 37: 2 Google Scholar The new CDC guidelines allow two approaches: a screening-based strategy (a modification of the AAP strategy), and a risk-factor approach (a modification of the ACOG approach). According to the screening-based approach all pregnant women should be screened at 35–37 weeks' gestation for anogenital GBS colonisation. Intrapartum antimicrobial prophylaxis (IAP) should be offered to all pregnant women identified as GBS carriers, even without risk factors. If the result of GBS culture is not known at the time of labour, IAP should be administered in the presence of risk factors: less than 37 weeks' gestation, more than 18 hours of membrane rupture, or temperature higher than 38°C. The alternative approach is a prophylaxis strategy based on the presence of the above mentioned intrapartum risk factors alone. Regardless of which strategy is used, women who were treated for symptomless GBS bacteriuria detected during pregnancy and women who previously have given birth to an infant with GBS disease should receive IAP. 1 Prevention of prenatal group B streptococcal diseaseA public health perspective. MMWR. 1996; 45 (RR-7): 1-24 Google Scholar