[Can we expect decreasing the incidence of patent ductus arteriosus (PDA) in the population of premature neonates who had received antenatal steroid therapy?]. / Czy u wczesniaków poddanych prenatalnej steroidoterapii mozna spodziewac sie ograniczenia czestosci wystepowania przetrwalego przewodu tetniczego (PDA)?

OBJECTIVES: The efficacy of antenatal steroid therapy (ANS--use with the recommendation from 1999; therapy repeated every 7-10 days; dexamethasone was used) on the incidence of RDS in neonates born before 34 weeks of gestation has been well documented in several studies. However, we know very little about the influence of ANS on patent ductus arteriosus (PDA). DESIGN: The purpose of this study was to assess the influence of ANS on the incidence of PDA in neonates born before 35 weeks of gestation. MATERIALS AND METHODS: The analysed population consisted of 425 newborns delivered at Research Institute Polish Mother's Memorial Hospital between 1996-1998. Patients were enrolled in three groups according to mode of ANS: Group I--complete ANS; Group II--partial ANS; Group III--without ANS (reference group, OR = 1). The complete ANS consisted of at least 24 mg of dexamethasone with a first dose given not earlier then 24 hours before delivery. The analysis was based on retrospective evaluation of patient's medical records. PDA was diagnosed during echocardiographic examination or during autopsy. The incidence and risk of significant PDA in enrolled groups were estimated. RESULTS: Use of complete ANS has no influence of the incidence of PDA. In the partial ANS group the risk of PDA (OR 1,89; p = 0,052 vs group III) was increased. Risk of PDA was also higher in patients born before 29 weeks of gestation, especially from the partial ANS group. CONCLUSIONS: The antenatal steroid therapy has influence of the incidence of PDA. We observed higher risk of PDA in the group of neonates born before 29 weeks of gestation and in the partial ANS group.