For hygiene reasons swimming pools require that babies wear suitable protection - normal suits offer no protection and ordinary diapers hold water, weighing the baby down. (kellyscloset.com)
This is important for obvious hygiene reasons and even more so important if you plan to use the pillow with a newborn. (pregnancypillowguide.com)
It is recommended to buy several for hygiene reasons, especially because they cost very little. (breedingbusiness.com)