Bed Climate for Infants and Their Mothers: From the Viewpoint of Absolute Humidity

Saturday, 29 July 2017

Rie Ikeda, PhD
Department of Nursing, Okayama Prefectural University, Soja, Japan
Sachiko Takahashi, EdD
Department of Nursing, Okayama Prefectural university, Soja, Japan


The microclimate created between bedding and the body is referred to as the "bed climate", with a bed temperature of 33ºC and relative humidity of 50-60% considered optimal. In 2005, the guidelines for the prevention of SIDS (sudden infant death syndrome) referred to the issue of sleep environments, including “the types of bed” and “overheating”. Wilson (2005) reported that infants’ bed climate of the eastern countries was warmer than them of the western countries. Overheating is one of the chief risk factors for SIDS1). The objective of the present study was that bed climate of Japanese infants and mothers is examined from the point of relative and absolute humidity for safe and comfortable sleep enviroment.


Data were collected from four infants (age range, 2-5 months) and their mothers. Bed climate and sleep-wake status while using the following three different mattress types (a cotton futon, cotton pad and a polyester futon) were monitored for three nights. A data logger was used to record the temperature and relative humidity associated with each mattress under the back and at the feet of each infant and mother for one minute. Absolute humidity was calculated from Relative humidity by computer. Sleep-wake status was assessed using an actigraph. Data associated with each bedding material for each night were then analyzed and compared.


Regarding bed climate, use of the cotton futon and the cotton pad resulted in lower bed temperature and humidity compared with the polyester futon. The bed climate was found to be influenced by the bedding when a water-proof sheet was used. Regarding infants’ sleep, total sleep time was longer with use of the cotton futon and pad. Sleep of mothers was influenced by sleep of their infants.


The cotton futon and the cotton pad appeared to provide favorable bed temperature and humidity. Use of them were indicated to positively affect the infants’ sleep.