A recent population-based cohort study conducted in Sweden has found a significant link between prenatal antibiotic exposure and an increased risk of Group B Streptococcus (GBS) disease in newborns. The study, initially reported by CIDRAP, was led by researchers from Sweden's Karolinska Institutet and the University of Antwerp in Belgium. It analyzed data from over one million singleton live births between 2006 and 2016, providing a robust dataset for its conclusions. The findings, published in the *Journal of Infection*, indicate that newborns exposed to antibiotics before birth had a 29% higher risk of developing GBS disease within four weeks postpartum compared to those not exposed. Specifically, the incidence of GBS disease was 0.86 per 1,000 live births in exposed newborns versus 0.66 per 1,000 in unexposed newborns, reflecting an adjusted odds ratio of 1.29. This increased risk was even more pronounced (34%) in pregnancies without any pre-existing GBS risk factors. The researchers observed the strongest association when antibiotic exposure occurred during the early third trimester of pregnancy. Group B Streptococcus is a common bacterium that can cause severe infections like sepsis, meningitis, and pneumonia in vulnerable newborns, potentially leading to life-threatening complications. Current prevention strategies primarily involve intrapartum antibiotic prophylaxis (IAP), administered *during labor*, to mothers at high risk or who test positive for GBS. These in-labor antibiotics have been effective in reducing early-onset GBS disease. However, this new research highlights a potential concern regarding antibiotics administered *before* labor. The widespread use of antibiotics during pregnancy, affecting approximately 25% of pregnancies globally, coupled with rising GBS resistance and the absence of a licensed maternal GBS vaccine, underscores the importance of these findings. The study authors suggest that prenatal antibiotic use might disrupt the natural balance of a baby's gut microbiota, potentially increasing susceptibility to infections. Experts emphasize the need for further studies to understand this association better and to refine guidelines for judicious antibiotic use during pregnancy. The implications are global, including for an Indian audience, as GBS is a concern for newborn health worldwide and antibiotic prescribing practices are common.