In a prospective study, we determined whether routine immediate tracheal aspiration at birth is necessary in meconium-stained but otherwise normal infants delivered vaginally and having a 1-minute Apgar score greater than 8. A total of 572 newborn infants who met these criteria were randomly allocated to one of two groups. All infants underwent oropharyngeal suctioning with a DeLee catheter while the head was still on the perineum. In group I (n = 308) suctioning of the trachea under direct vision was performed instantly at birth; in group II (n = 264) this procedure was not done. There was no mortality among infants in the study, but morbidity, mainly pulmonary and laryngeal disorders, occurred in six of 308 group I infants and in none of the group II infants (P less than 0.025). Immediate tracheal suction is not a harmless intervention, and should be considered superfluous in a vigorous term neonate born with meconium-stained amniotic fluid.