Antibiotic use in pregnancy and drug-resistant infant sepsis

OBJECTIVE: We sought to evaluate the effect of antepartum and intrapartum a ntibiotic use on antimicrobial-resistant neonatal sepsis. STUDY DESIGN: We analyzed perinatal outcomes for 8474 pregnancies (8593 liv e births) delivered at 6 hospitals. Data were collected regarding maternal antibiotic use and perinatal course, neonatal cultures, and outcomes. The d iagnosis of confirmed neonatal sepsis required at least one positive blood or cerebrospinal fluid culture. Neonatal cultures were evaluated on the bas is of the occurrence and timing of maternal antibiotic exposure. RESULTS: There were 96 neonates with confirmed sepsis (11.2/1000 live birth s). Sepsis was 19.3-fold more common after preterm birth (57 vs 3.1/1000, P <.001), with 76% of septic infants being delivered preterm. Forty-five perc ent of pathogens were ampicillin resistant. Ampicillin resistance increased with preterm birth (50% vs 26%: P=.04), antepartum antibiotics (57% vs 34% ; P=.03), intrapartum antibiotics (55% vs 28%; P<.01), and any prenatal ant ibiotic exposure (52% vs 22%; P=.01). Infection with an organism resistant to at least one maternal antibiotic was more common with intrapartum antibi otic exposure than with antepartum exposure only (57% vs 17%, P=.01). Regar ding early-onset sepsis (n=55), ampicillin resistance was more common with intrapartum antibiotics (50% vs 16%, P<.01), and resistance to at least one maternally administered antibiotic was more frequent with intrapartum expo sure (56.7% vs 0%; P<.01). CONCLUSIONS: Maternal antibiotic treatment is associated with neonatal seps is by organisms resistant to ampicillin and to maternally administered anti biotics.