Analysis of noise and vibration from infant incubators (models Medicor and CN2) revealed average noise levels (peak values) of 60 dB (A-weighted) and 73.5 dB (linear) and values for vibration where the infant's head normally rests were 0.065 m/sec2 (A-weighted) and 0.14 m/sec2 (linear), and at the infants' feet were 0.105 m/sec 2 (A-weighted) and 0.58 m/sec2 (linear). On the basis of present knowledge of the physiologic effects of noise and vibration, we discuss the influence of long-term noise and vibration exposures on the neonate; they provide a threat to carbohydrate, aliphatic compound and protein-enzymatic metabolic transformations and produce changes in cardiovascular, pituitary--adrenal axis and auditory systems.