Maternal use of antibiotics during pregnancy may increase the likelihood of babies developing Group B Streptococcus (GBS) disease, a common bacterial infection. While these bacteria typically reside harmlessly in the gut or genital tract, they can lead to severe infections in newborns, older adults, and those with weakened immune systems, causing conditions like sepsis, meningitis, and pneumonia.
A study conducted by an international team from Karolinska Institutet in Sweden and University of Antwerp in Belgium revealed that prenatal exposure to antibiotics was connected to a higher risk of neonatal GBS disease within four weeks of birth, with the strongest association seen in early third-trimester exposure. The researchers emphasized that prenatal antibiotic exposure could elevate the risk of GBS in neonates, especially those not covered by risk-based intrapartum prophylaxis.
The study, a population-based cohort analysis of all singleton live births in Sweden from 2006 to 2016 using national registers, found that among 1,095,644 liveborn singletons, 24.5 percent were exposed to antibiotics. The incidence of GBS was higher in exposed neonates compared to unexposed ones, particularly in those without GBS risk factors.
According to the researchers, this study is the first to explore the link between prenatal antibiotic exposure and neonatal GBS disease risk. The findings aligned with previous Nordic studies indicating a 16-34 percent increased risk of infections in early childhood following prenatal antibiotic exposure. Notably, the study highlighted that GBS-active antibiotics administered close to delivery did not provide protection, and the association of prenatal antibiotic exposure with neonatal GBS disease seemed to be influenced by the presence of clinical GBS risk factors.
The team suggested that neonates without established GBS risk factors might benefit more from limiting prenatal antibiotic exposure. They called for further research and emphasized the importance of enhanced monitoring of neonates not covered by existing GBS prevention guidelines, particularly those exposed to antibiotics during the early third trimester.
