I am an old enough pediatrician to have seen a number of sleep fads come and go in my career. I recall a device that gently shook the crib and made the noise similar to a car ride that was very popular back in the 80’s. I also recall, a set of springs that were fitted to the bottom of the crib so as to create a rocking motion each time the baby moved. Who could forget the stuffed animal that had placenta noises or heart beat sounds emanating to help the infant replicate the womb-like environment in their crib. The current trends in infant sleep aides seem to be swaddle devices and white noise machines, to a large degree popularized by Dr. Harvey Karp, a pediatrician in California.
It was with great interest to me when I recently read a study that has questioned the safety of the white noise machines that are currently sold in the US. The authors recorded the decibel level of a variety of these machines and found that, at close distances, the amount of noise they produce could potentially cause hearing loss in an infant, especially if they were run all night. Currently, experts recommend that noise in hospital nurseries not exceed 50 decibels but many of these machines tested reached 85 decibels sound levels, far above what is considered safe. Exposure to noise of that level over an extended period of time can potentially cause permanent hearing loss.
Parents need to use caution when they introduce any external device into an infant’s sleep ritual as we have recently been reminded with revelations about swaddle devices and now sound machines. Yes, there might be some short-term advantages from these devices but those unintended consequences often come back to haunt us. In the case of white noise machines, exposure to a lot of noise is clearly a limiting factor. Although difficult for many infants, maybe learning to settle oneself down and control one’s own environment by creating their own “Comfortable sleep environment” is an important learning step for infants.