it is a prospective randomized simple-blinded pilot trial with the principal aim to compare efficacy and tolerance between oral ibuprofen and intravenous ibuprofen in early curative closure of PDA in very low birth weight infants. The likelihood of ductal closure with only one or two doses of treatment is a secondary objective.

We calculated that a study group of 62 patients would be necessary for the study to be able to detect a difference of at least 25 percentage points in the closure rate between the oral ibuprofen and intravenous ibuprofen groups, assuming a closure rate of 65 percent with intravenous ibuprofen, with a p value of 0, 05 and a power of 80 percent.Patients (gestational age, 25 to 32 weeks) with echocardiographically confirmed patent ductus arteriosus and respiratory distress will randomly be assigned to receive one (10 mg / kg), two (10 mg / kg followed 24 hours after by 5 mg /kg) or three (10 mg / kg followed at 24-hour intervals by two doses of 5 mg /kg each) doses of either intravenous ibuprofen (group I, n = 32) or oral ibuprofen (group O, n = 32), starting on the third day of life. The rate of ductal closure, side effects, complications, and the patients' clinical course will be recorded.

Inclusion Criteria:

• a gestational age < 32 weeks
• a birth weight < 1500g
• a postnatal age between 48 and 96 hours, a respiratory distress requiring more than 25 % of oxygen supplementation
• an echocardiographic evidence of left to right significant shunting PDA

Exclusion Criteria:

• a right-to-left shunting
• major congenital anomalies
• IVH grade 3-4
• a tendency to bleed (defined by the presence of blood in the endotracheal aspirate, gastric aspirate, stools or urines and / or oozing from puncture sites)
• a serum creatinine level >140µmol/l, a serum urea nitrogen > 14 µmol/l and a platelet count < 60000/mm3.