“…The technique has now been shown to be quite safe in premature infants, neonates, children, and adults, including antenatal patients (Beard, McCoy, Newton, and Clayton, 1965 ;Nelson and Peters, 1965;Pryles, 1965;Stamey, Govan, and Palmer, 1965;Newman, O'Neill, and Parker, 1967;McFadyen and Eykyn, 1968).…”