The aim of the study was to determine whether morphine sulfate administration is associated with an increased risk of necrotizing enterocolitis (NEC) in preterm infants supported by mechanical ventilation due to respiratory failure. The matched case-control retrospective study was carried out at the Neonatal Intensive Care Unit (NICU) of the University Clinical Center Sarajevo, on 122 preterm infants classified into total NEC group and control group. The total NEC group was further divided into medical NEC and surgical NEC subgroups. The association between the use and duration of morphine sulfate infusion and the development of NEC was evaluated in both unadjusted and adjusted analysis. Preterm infants who developed NEC were on mechanical ventilation more frequently compared to premature infants without signs of NEC (Mann- Whitney U test; p=0.0031). A positive correlation between the frequency of receiving morphine sulfate and the development of NEC was observed (Chi square test of independence; p=0.0001). The risk of NEC in preterm infants was increased by the use of morphine sulfate. Validation of this observation in other populations is warranted.

Keywords: mechanical ventilation, morphine sulfate, necrotizing enterocolitis, opioids, preterm infants