Presence of Patent Ductus Arteriosus is detrimental to an infant born prematurely. The primary objective is to study the efficacy of Paracetamol (proposed new treatment) in treating haemodynamic significant Patent Ductus Arteriosus (hsPDA) in comparison to Ibuprofen (current standard treatment) in preterm infants. Outcome of such treatment will check on the conversion of hsPDA to non-hsPDA. All preterm infants (born at \<32 weeks gestational age or birth weight \< 1500 grams) with haemodynamically significant patent ductus arteriosus (hsPDA) who are ≤ 28 days old will be included over 2 years. Sample size 32. Secondary outcomes of this study will compare 1\) BPD (broncho-pulmonary dysplasia) free survival at 36 weeks post menstrual age (PMA), 2) incidence of complications of prematurity in each group and 3) to record any evidence of adverse effects with Paracetamol or Ibuprofen.