Surfactant is produced in the lungs to decrease surface tension of the alveoli and help keep them open during expiration. It is not produced endogenously until roughly 34 weeks of gestation. Therefore, the neonate delivered at 29-weeks estimated GA who requires mechanical ventilation may benefit from surfactant therapy. Meconium inhaled into the lungs deactivates surfactant. Therefore, the full-term neonate with meconium aspiration syndrome (MAS) who requires mechanical ventilation may also benefit from surfactant therapy. The neonate delivered at 35-weeks estimated GA with transient tachypnea of the newborn and the full-term baby with gastroschisis do not require surfactant.