Background: Although, patent ductus arteriosus (PDA) is associated with significant morbidity due to hemodynamic instability in preterm infants, the effect of ductus closure on mortality and morbidity is a controversial issue. The aim is to evaluate the efficacy of oral and intravenous (IV) ibuprofen treatment on ductal closure and effects on mortality and bronchoplumonary dysplasia. Materials and Methods: The medical records of 292 premature infants treated at Ege University Neonatal Intensive Care Unit were retrospectively evaluated. Patients were classified into 3 groups as; No PDA, hemodynamically insignificant PDA (hiPDA) and hemodynamically significant PDA (hsPDA) according to the presence and hemodynamical significance of PDA by echocardiography. hsPDA group was treated with IV or oral ibuprofen. Results: Patent ductus arteriosus was diagnosed by routine echocardiography in 145 patients, of whom 78 (53.7%) had hsPDA. All 65 infants with hiPDA had spontaneous PDA closure. Echocardiographic measurements were similar to those patients treated with oral or IV ibuprofen, as in the response rate to treatment without serious adverse effects. The presence of respiratory distress syndrome, surfactant therapy, late sepsis, bronchopulmonary dysplasia (BPD) and mortality rates were significantly higher in patients with hsPDA. However, with stepwise logistic regression; 5th min Apgar score (odds ratio [OR], 1.321, 95% confidence interval [CI], 1.063-1.641, P = 0.012) and gestational age (OR, 1.422, 95% CI, 1.212-1.662, P < 0.001) were the only significant variables associated with mortality. Gestational age (OR, 0.680, 95% CI, 0.531-0.871, P = 0.002) was the only significant variable associated with BPD shown with logistic regression. Conclusion: Ibuprofen treatment is effective for hsPDA closure with minimal side effects. HiPDA can close spontaneously; therefore treatment decision should be individualized. However, medical treatment of PDA does not reduce mortality and BPD.