Abstract
The ciliary beat frequencies of 31 newborns and 14 adults were measured in vitro by a photodiode method at body temperature (37 degrees C). The mean (SD) neonatal ciliary beat frequency (12.7 (0.82) Hz) was faster than that in adults (11.1 (0.84) Hz) (p less than 0.01). Increased ciliary beat frequency may be advantageous during the neonatal period.