We aimed to study whether national and local antibiotic stewardship projects have reduced the antibiotic use in newborns and to monitor potential changes in adverse outcomes.
In a nationwide, population-based study from Norway, we included all hospital live births from 34 weeks' gestation (n = 282 046) during 2015 to 2019. The primary outcome was the proportion of newborns treated with antibiotics from 0 to 28 days after birth. The secondary outcomes were the overall duration of antibiotic treatment and by categories: culture-positive sepsis, clinical sepsis, and no sepsis.
A total of 7365 (2.6%) newborns received intravenous antibiotics during the period, with a reduction from 3.1% in 2015 to 2.2% in 2019 (30% decrease; P < .001). Hospitals with antibiotic stewardship projects experienced the largest reduction (48% vs 23%; P < .001). We found a small decrease in the median duration of antibiotic treatment in newborns without sepsis from 2.93 to 2.66 days (P = .011), and geographical variation was reduced during the study period. The overall number of days with antibiotic treatments was reduced by 37% from 2015 to 2019 (119.1 of 1000 vs 75.6 of 1000; P < .001). Sepsis was confirmed by blood culture in 206 newborns (incidence rate: 0.73 cases per 1000 live births). We found no increase in sepsis with treatment onset >72 hours of life, and sepsis-attributable deaths remained at a low level.
During the study period, a substantial decrease in the proportion of newborns treated with antibiotics was observed together with a decline in treatment duration for newborns without culture-positive sepsis.