Peripartum bacteremia in the era of group B streptococcus prophylaxis.

OBJECTIVE To define the microbial epidemiology and clinical risk factors associated with peripartum bacteremia in the era of group B streptococcus prophylaxis. METHODS We identified all cases of maternal bacteremia occurring during the peripartum time period (defined as from 7 days before delivery until 30 days after delivery) in a large maternity center from 2000 to 2008. Chart review was performed to determine the clinical factors associated with bacteremia. RESULTS During the study period, blood cultures were obtained from 1,295 febrile peripartum women (1.6% of all parturients); 172 of 1,295 febrile peripartum women (13.3%) had bacteremia (2.2 cases per 1,000 deliveries) with 194 microbial isolates and 1 yeast. The most frequent bacterial isolates were Escherichia coli (35.9%), enterococci (23.6%), and anaerobic species (9.2%); group B streptococcus was isolated in only eight cases (4.1%). Clinical diagnoses among infected women included endometritis (56%), chorioamnionitis (21%), and urosepsis (8%). Among women with endometritis, 77% underwent cesarean delivery (compared with vaginal delivery; relative risk [RR] 10.85, 95% confidence interval [CI] 6.75-17.45) and 39% delivered at less than 37 weeks of gestation (compared with 37 weeks or more; RR 3.21, 95% CI 2.42-4.25). Severe maternal complications of bacteremia were noted; six women required intensive care unit admission, five women had development of ileus, and one death occurred because of urosepsis. CONCLUSION In the era of group B streptococcus prophylaxis, E coli and enterococci are the most frequent bacteria isolated in peripartum bacteremia. Group B streptococcus accounted for only 4% of cases. LEVEL OF EVIDENCE III.