Antenatal antibiotic exposure in preterm infants with necrotizing enterocolitis

Objective:to determine whether an association exists between antenatal antibiotic exposure and incidence of necrotizing enterocolitis (nec) in low birth weight infants.study design:a retrospective case-control study was performed on all infants with a diagnosis of nec born at our institition between 1988 and 2006. medical histories of all infants with a diagnosis of nec ⩾bell's stage iia and matched controls without nec were reviewed. maternal and neonatal characteristics were compared using the mantel-haenszel chi-square procedure, and logistic regression models were constructed to account for confounding.result:clinical data for 97 matched pairs were analyzed. the adjusted odds ratio (or) for antenatal exposure to ampicillin was significantly greater for infants who developed nec (or 2.3, 95% confidence interval 1.1, 4.8, p=0.003) than for control infants.conclusion:infants who developed nec were more likely to have a history of in utero exposure to ampicillin in the immediate antepartum period than infants who did not develop nec.