Prevention of early-onset invasive neonatal group B streptococcal disease in a private hospital setting: The superiority of culture-based protocols

Objective: In a large private tertiary care hospital we compared the two different approaches to group B streptococcal screening and intrapartum chemoprophylaxis suggested by The American College of Obstetricians and Gynecologists, the American Academy of Pediatrics, and the Centers for Disease Control and Prevention: risk factor–based protocol and culture-based protocol. Study Design: A 2-year baseline period was followed by sequential prospective observational studies of the impacts of two different group B streptococcal management protocols, 3 years with the risk-based approach and 2 years with the culture-based approach of universal screening at 35 to 37 weeks’ gestation. Results: During the baseline period the rate of early-onset group B streptococcal infection was 1.1 cases per 1000 births (n = 8 cases per 6829 births). With the risk-based strategy the rate was also 1.1 cases per 1000 births (15 cases/13,270 births). After we switched to the culture-based protocol for 2 years, there were no cases of early-onset group B streptococcal infections among 9304 births (P = .001; χ2 = 10.9). There were no increases in other early-onset infections or in antibiotic resistance. Conclusions: In our setting, which included good prenatal care and good communication between laboratories and the hospital, the approach based on maternal culture at 35 to 37 weeks’ gestation and treatment during labor of all patients with positive results significantly reduced early-onset group B streptococcal infections without increasing infections from resistant organisms. (Am J Obstet Gynecol 2000;182:1344-54.)