The most common predisposing factors which led to mechanical ventilation were pulmonary disorders and birth asphyxia. Among lung disorders, respiratory distress syndrome was the most common cause of mechanical ventilation (Fig. 3). It was seen in 60.25% of mechanically ventilated neonates in the present study. In 102 neonates with pneumothorax, 51 (54.3%) cases had respiratory distress syndrome. Meconium aspiration syndrome and diaphragmatic hernia are the other most common pulmonary causes for mechanical ventilation.