In four newborn patients skin-lesions were found on the knee as a result of burns from hot-water bottles. Hot-water bottles are frequently used to fight and prevent hypothermia in newborns. This method is considered safe. We studied skin temperature in newborns with heat sensors on the skin and showed that the temperature of the skin can rise up to 50.8°C due to contact with a hot-water bottle wrapped in a cloth. Hot-water bottles therefore should be handled with care to avoid possible burns in newborns. We recommend that hot-water bottles be wrapped in a cloth and sufficient space be maintained between the hot-water bottle and the newborn to prevent pressure points, and both the hot-water bottle and the baby be checked regularly.