A cohort study of intrapartum group B streptococcus prophylaxis on atopic dermatitis in 2-year-old children.

<bold>Objective: </bold>To understand the occurrence of atopic dermatitis (AD) in children aged 2 years on exposure to maternal group B streptococcus (GBS) antibiotic prophylaxis (IAP).<bold>Design: </bold>Retrospective cohort study of 2909 mother-child pairs.<bold>Setting: </bold>Taixing People's Hospital in Eastern China.<bold>Participants: </bold>Term infants born 2018-2019, followed longitudinally from birth to 2 years.<bold>Exposures: </bold>The GBS-IAP was defined as therapy with intravenous penicillin G or ampicillin or cefazolin ≥ 4 h prior to delivery to the mother. Reference infants were defined as born without or with other intrapartum antibiotic exposure.<bold>Outcomes: </bold>The logistic regression models were employed to analyze the effect of intrapartum GBS prophylaxis on AD in 2-year-old children during delivery. Analysis was a priori stratified according to the mode of delivery and adjusted for relevant covariates.<bold>Results: </bold>The cohorts showed that preventive GBS-IAP was potentially associated with increased incidence of AD in children delivered vaginally according to logistic regression models before and after covariate-adjusted treatment (OR: 6.719,95% CI: 4.730-9.544,P < 0.001;aOR: 6.562,95% CI: 4.302-10.008, P < 0.001).<bold>Conclusion: </bold>Prophylactic treatment of intrapartum GBS may raise the risk of AD in vaginally delivered children. These findings highlight the need to better understand the risk between childhood AD and current GBS-IAP intervention strategies. [ABSTRACT FROM AUTHOR]