['Data comparing the effectiveness of high-frequency oscillatory ventilation and of conventional mechanical ventilation in the treatment of respiratory distress syndrome of very low birth weight infants are, to date, still matter of debate. We investigated the effects of first intention high-frequency oscillatory ventilation or conventional mechanical ventilation support on selected primary and secondary outcomes in very low birth weight infants complicated by respiratory distress syndrome in which antenatal glucocorticoid prophylaxis was not performed.', 'Multicenter randomized control trial.', 'Three tertiary centers of neonatal intensive care units from December 2004 to December 2007.', 'Eighty-eight very low birth weight infants complicated by respiratory distress syndrome, without antenatal glucocorticoids, supported by first intention high-frequency oscillatory ventilation (n = 44) or conventional mechanical ventilation (n = 44).', 'All newborns were monitored by standard monitoring procedure, including routine laboratory variables, neurologic patterns, and ultrasound imaging. Primary outcomes were: the length of ventilatory support, the need of reintubation, and the length of nasal continuous positive airway pressure support in the postextubation period. Secondary outcomes were: the length of stay in neonatal intensive care unit and in hospital, death before discharge, adverse short- and long-term pulmonary and neonatal outcomes, and the need for a second dose of surfactant and of postnatal glucocorticoid treatment.', 'High-frequency oscillatory ventilation infants showed a significant lower duration (p < .001 for all) of ventilator dependency, lower need of reintubation and of duration of nasal continuous positive airway pressure support in the postextubation period. Among secondary outcomes in the high-frequency oscillatory ventilation infants, the need of a second dose of surfactant administration, and the length of stay in the neonatal intensive care unit and in hospital were significantly lower (p < .05 for all).'] Do first intention high-frequency oscillatory and conventional mechanical ventilation in premature infants without antenatal glucocorticoid prophylaxis?