The effect of humidity on survival of newly born premature infants.

A controlled clinical trial was conducted to study the effects of two conditions of humidity upon respiratory symptoms, death rate and necropsy findings among premature infants in the first 5 days of life. Infants who were placed in environments of "80-90% relative humidity," which was achieved without the use of mist, had more rapid respiratory rates, higher body temperatures and a lower death rate than controls in "30-60% relative humidity." The nature of the mechanisms underlying the observed associations is a matter of conjecture which is under further study.