Incubators may alter the heart rates of newborn babies, causing them more harm than good when they are in a vulnerable state, a new study says.

The findings showed a significant increase in heart-rate variability among babies that were exposed to the electromagnetic waves produced by an incubator's fan motor.

Heart-rate variability is the beat-to-beat variation in the heart rate. While a fluctuation in heart rate is normal, both an increased and a decreased heart-rate variability are indicators of stress on the body.

In the small study, 27 babies were exposed to the incubator's motor in two five-minute increments, separated by a five-minute period when the motor was off.

The other 16 babies were exposed to a tape recording of an incubator motor in the same time increments, while the actual motor remained off.

There was no difference in heart rate variability among the babies in the tape-recording group.

Because premature babies lack the energy necessary to keep their bodies at the ideal temperature of 37 degrees Celsius, they are put in incubators to keep warm. A heater warms air that is circulated by the fan throughout the incubator.

While this study was not conducted on premature babies, the findings indicate that an incubator could in fact add more stress to a baby's system. This could impact care for preemies, who can remain in incubators for weeks or months after they are born.

Previous research has suggested a link between exposure to electromagnetic fields (EMFs) and various health effects in humans. For instance, scientists have shown that EMFs from cellphones alter brain activity.

In their study, the researchers, from the University of Siena, in Italy, concluded that the medical community needs to next research what long-term effects the EMFs of incubators have on babies.

"These observations suggest that newborns should be one case in which a policy of prudent avoidance of an EMF is warranted, perhaps because no study has so far excluded the possibility of negative consequences of their chronic exposition to a high EMF in incubators," the authors wrote.

The findings were published in the journal Fetal and Neonatal Edition of Archives of Disease in Childhood.

This research comes at a time when preemie care is a hot topic among scientists. A recent study found that skin-to-skin contact, or so-called 'Kangaroo Care,' between a mother and her preemie proved beneficial in relieving the baby's pain after having blood drawn from its heel.

Abstract:

Electromagnetic fields produced by incubators influence heart rate variability in newborns

C V Bellieni, M Acampa, M Maffei, S Maffei, S Perrone, I Pinto, N Stacchini, G Buonocore

Background: Incubators are largely used to preserve preterm and sick babies from postnatal stressors, but their motors produce high electromagnetic fields (EMFs).

Newborns are chronically exposed to these EMFs, but no studies about their effects on the fragile developing neonatal structure exist.

Aim: To verify whether the exposure to incubator motor electric power may alter autonomous nervous system activity in newborns.

Material and methods: Heart rate variability (HRV) of 43 newborns in incubators was studied. The study group comprised 27 newborns whose HRV was studied throughout three 5-minute periods: with incubator motor on, off, and on again, respectively. Mean HRV values obtained during each period were compared. The control group comprised 16 newborns with constantly unrecordable EMF and exposed to changes in background noise, similar to those provoked by the incubator motor.

Results: Mean (SD) total power and the high-frequency (HF) component of HRV increased significantly (from 87.1 (76.2) ms2 to 183.6 (168.5) ms2) and the mean lowfrequency (LF)/HF ratio decreased significantly (from 2.0 (0.5) to 1.5 (0.6)) when the incubator motor was turned off. Basal values (HF=107.1 (118.1) ms2 and LF/ HF=1.9 (0.6)) were restored when incubators were turned on again. The LF spectral component of HRV showed a statistically significant change only in the second phase of the experiment. Changes in background noise did not provoke any significant change in HRV.

Conclusion: EMFs produced by incubators influence newborns' HRV, showing an influence on their autonomous nervous system. More research is needed to assess possible long-term consequences, since premature newborns may be exposed to these high EMFs for months.