Is baby too warm? The use of infant clothing, bedding and home heating in Victoria, Australia.

doi:10.1016/S0378-3782(97)00085-6

Early Human Development

Volume 51, Issue 2, 29 May 1998, Pages 93-107

https://doi.org/10.1016/S0378-3782(97)00085-6 Get rights and content

Abstract

Overheating of infants has been associated with a raised risk for sudden infant death syndrome (SIDS). Data on the use of heating, bedding and clothing and other measures affecting the thermal environment of 4 week old infants were collected at a home interview for infants of women born in Australia (Anglo-Celtic background), in Southern Europe, in Asia and of women who had a planned out-of-hospital birth. These groups have different risks of SIDS not explained by the classic social and perinatal risk factors nor associated with the currently promoted 'new' risk factors. Thermal insulation of the infant's bedding and clothing and excess thermal insulation (for any observed room temperature) were calculated. Bed sharing differed significantly between the groups as did the use of a sheepskin, tucking in firmly, the closing of doors and windows and the use of heating in the infant's room. After stratifying by bed sharing practice and season of interview, it was found that bed sharing infants had more thermal insulation than those sleeping alone irrespective of season of interview. Infants sleeping alone in the Asian-born and Southern European-born groups were kept warmer than infants in the other two groups. Cultural factors appear to affect the thermal environment in which infants are raised. Some bed sharing infants in all four groups were inappropriately warm, particularly in colder weather, but this was more likely in the Asian-born (low risk) group than in the home birth (high risk) group. These results do not explain the differences in SIDS incidence between the groups.

Introduction

The differences in the incidence of sudden infant death syndrome (SIDS) between groups from different ethnic and cultural backgrounds in the State of Victoria, cannot be explained by the classic social and perinatal risk factors 1, 2, nor are they associated with the 'new' risk factors: the prone sleeping position, not being fully breastfed, exposure to cigarette smoke and bed sharing [3]. Links between climatic temperature and SIDS incidence have been established 4, 5and studies in several countries have recorded how families respond to changes in ambient temperature, in regard to the amount and type of bedding and clothing they use for their infants and in the use of heating in the home 6, 7, 8, 9, 10. Overheating of infants, found to be generally more common in winter, has been suggested as a possible trigger for SIDS 11, 12, 13.

Data were collected at a home interview in a project which examined the family environments of four groups of women and their infants who are at different risks of SIDS 1, 2: a reference group of 200 Australian-born women of Anglo-Celtic background (SIDS incidence 2.04/1000), 56 women born in Southern Europe (0.58/1000) and 101 women born in Asia (0.97/1000) whose infants have a very low risk of SIDS, and 102 homebirth women whose infants have a high risk of SIDS (14.6/1000). All the infants were between 3 and 5 weeks of age at the time of interview. This paper reports on analysis of data relating to the infant's thermal environment and explores the differences in the distribution of these variables between the groups.

Section snippets

Methods

A detailed account of the methodology used in the project and some maternal and infant characteristics by group have been published [3]. Further maternal and infant factors are included in this paper for comparison with other studies [6].

At interview, mothers were asked about the infant's usual sleep position, sleep location and practice in regard to 'swaddling' and 'tucking in'. Actions they had taken previously or expected to take in order to control the thermal environment of the infant were

Results

Data collected between January 1991 and April 1993 from 459 interviews, 52% of which were conducted in the colder months (May to October) are presented. Comparisons of the four groups on some descriptive variables are shown in Table 2. There were significant differences for all variables except proportions of male infants. Infants of women born in Southern Europe (SE) and Asia (As) were of lower birthweight and were more likely to be first born. Only one Asian-born mother was smoking currently:

Starting point

The rationale for this study was the significant differences in SIDS incidence between the four study groups that existed in 1989. During the period of data collection community awareness campaigns about SIDS 'new' risks factors were undertaken. Subsequently there have been marked decreases in SIDS incidence attributed particularly to changes in the practice of prone sleeping [18]. For other factors, and with particular relevance to this study, that of the thermal environment of the infant, the

Conclusion

We have shown that there are differences between the four groups in the emphasis placed on keeping infants warm and have evidence that cultural traditions and beliefs may influence these attitudes and behaviours. Our excess tog data suggest that some infant bed sharers in all four groups were inappropriately warm, particularly in colder weather, but this was more likely in the Asian-born (low risk) group than in the homebirth (high risk) group. Indeed, it appears that the majority of infants in

Acknowledgements

The authors wish to thank Bronwyn Handfield, Jane Yelland and the midwifery staff at Monash Medical Centre for their help with recruitment; Professor Terry Dwyer, Dr Anne-Louise Ponsonby of the Menzies Centre for Population Health Research, University of Tasmania, who kindly allowed us to use the Tasmanian Infant Health Study protocols and Ms Jenny Cochrane (of the same Centre) who coded the clothing and bedding togs; the homebirth practitioners who gave their support and all the women who

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The influence of bed-sharing on infant physiology, breastfeeding and behaviour: A systematic review
2019, Sleep Medicine Reviews
Citation Excerpt :
Tables S1–6 summarise the data on bed-sharing definition for each paper. Methodological quality of papers included for relevant outcomes ranged from four [39,46,58,70,73–75] to nine points [13,40,41] with a mean of six. A maximum of nine points was only possible if studies included a control group, otherwise the maximum score was seven as scored in eight studies [6,54,61–63,76–79].
This review aimed to better understand the underlying physiology of the risks and benefits of bed-sharing. Eight databases were searched using terms relating to adult–infant/baby, bed-sharing/co-sleeping combined with outcome terms for physiology, sleep, cardiovascular, respiratory, temperature and behaviour. Of 836 papers identified, 59 papers representing 48 cohorts met inclusion criteria. Objective data using various methodologies were available in 27 papers and subjective data in 32 papers. Diverse measures were reported using variable definitions of bed-sharing. Identified physiological and behavioural differences between bed-sharing and cot-sleeping included increased behavioural arousals, warmer in-bed temperatures and increased breastfeeding duration in bedshare infants as well as differences in infant overnight sleep architecture, cardiorespiratory control and cortisol responses to stress.
We concluded that many differences are context-specific, and dependent on the subjective view of the parents and their cultural values. Objective risk arises if the infant is unable to mount an appropriate physiological or behavioural response to their micro-environment. More studies in the bed-sharing setting are needed to identify infant risk, the potential benefits of a safer environment, and how bed-sharing interacts with infant care practices other than sleep.
Parent-child bed-sharing: The good, the bad, and the burden of evidence
2017, Sleep Medicine Reviews
The practice of parent and child sharing a sleeping surface, or ‘bed-sharing’, is one of the most controversial topics in parenting research. The lay literature has popularized and polarized this debate, offering on one hand claims of dangers, and on the other, of benefits – both physical and psychological – associated with bed-sharing. To address the scientific evidence behind such claims, we systematically reviewed 659 published papers (peer-reviewed, editorial pieces, and commentaries) on the topic of parent-child bed-sharing. Our review offers a narrative walkthrough of the many subdomains of bed-sharing research, including its many correlates (e.g., socioeconomic and cultural factors) and purported risks or outcomes (e.g., sudden infant death syndrome, sleep problems). We found general design limitations and a lack of convincing evidence in the literature, which preclude making strong generalizations. A heat-map based on 98 eligible studies aids the reader to visualize world-wide prevalence in bed-sharing and highlights the need for further research in societies where bed-sharing is the norm. We urge for multiple subfields – anthropology, psychology/psychiatry, and pediatrics – to come together with the aim of understanding infant sleep and how nightly proximity to the parents influences children's social, emotional, and physical development.
Thermal insulation and SIDS - An investigation of selected 'Eastern' and 'Western' infant bedding combinations
2005, Early Human Development
Differences in the incidence of SIDS between ‘Western’ and ‘Eastern’ countries has been attributed to cultural practices, which may affect the infants care and thermal environment.
The purpose of this work was to estimate for selected ‘commonly’ used bedding, sleep positions and practices in Japan, Korea and New Zealand, the intrinsic ‘dry’ thermal resistance of bedding. Insulation levels are also discussed in the context of published information about the thermal environment in which the bedding is likely to be used.
Selected Japanese, Korean and New Zealand bedding was loosely tucked over an infant manikin in the lateral, prone and supine sleep positions. Thickness in use was measured, and intrinsic ‘dry’ thermal resistance estimated using the Wilson Laing model which accommodates the effect on insulation of the three-dimensional arrangement of bedding combinations during use.
Thickness of under- and upper-bedding varied among countries with thickness and estimated ‘dry’ thermal resistance of the upper-bedding affected by the type/combination of bedding and the infants sleep position. Insulation levels are discussed in relation to environmental conditions within and among countries and between seasons. Further information on thermal environments, bedding combinations used and care practices within both Asian and Western countries is needed.
‘Eastern’ infants appear likely to be generally covered in bedding combinations of greater insulation than those used to cover ‘Western’ infants in comparable seasons. Differences existed between insulation of the Japanese and Korean bedding combinations investigated. Lower rates of SIDS apparent in ‘Asian’ populations do not appear attributable to use of lower levels of bedding insulation only.
International Child Care Practices Study: infant sleeping environment
2001, Early Human Development
Background: The International Child Care Practices Study (ICCPS) has collected descriptive data from 21 centres in 17 countries. In this report, data are presented on the infant sleeping environment with the main focus being sudden infant death syndrome (SIDS) risk factors (bedsharing and infant using a pillow) and protective factors (infant sharing a room with adult) that are not yet well established in the literature.
Methods: Using a standardised protocol, parents of infants were surveyed at birth by interview and at 3 months of age mainly by postal questionnaire. Centres were grouped according to geographic location. Also indicated was the level of SIDS awareness in the community, i.e. whether any campaigns or messages to “reduce the risks of SIDS” were available at the time of the survey.
Results: Birth interview data were available for 5488 individual families and 4656 (85%) returned questionnaires at 3 months. Rates of bedsharing varied considerably (2–88%) and it appeared to be more common in the samples with a lower awareness of SIDS, but not necessarily a high SIDS rate. Countries with higher rates of bedsharing appeared to have a greater proportion of infants bedsharing for a longer duration (>5 h). Rates of room sharing varied (58–100%) with some of the lowest rates noted in centres with a higher awareness of SIDS. Rates of pillow use ranged from 4% to 95%.
Conclusions: It is likely that methods of bedsharing differ cross-culturally, and although further details were sought on different bedsharing practices, it was not possible to build up a composite picture of “typical” bedsharing practices in these different communities. These data highlight interesting patterns in child care in these diverse populations. Although these results should not be used to imply that any particular child care practice either increases or decreases the risk of SIDS, these findings should help to inject caution into the process of developing SIDS prevention campaigns for non-Western cultures.
Hyperthermia and Heat Stress as Risk Factors for Sudden Infant Death Syndrome: A Narrative Review
2022, Frontiers in Pediatrics
Using the capability approach to evaluate energy vulnerability policies and initiatives in Victoria, Australia
2021, Local Environment

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View full text

Is baby too warm? The use of infant clothing, bedding and home heating in Victoria, Australia.

Abstract

Introduction

Section snippets

Methods

Results

Starting point

Conclusion

Acknowledgements

Early Hum. Dev.

Lancet

Lancet

Ethnic differences in the incidence of the sudden infant death syndrome (SIDS) in Victoria, Australia 1985–1989

Paediatr. Perinat. Epidemiol.

Sudden infant death syndrome: factors contributing to the difference in incidence between Victoria and Tasmania

Med. J. Aust.

Climatic temperature and variation in the incidence of sudden infant death syndrome between the Australian States

Med. J. Aust.

How mothers keep their babies warm

Arch. Dis. Childh.

Characteristics of the infant thermal environment in the control population of a case-control study of SIDS

J. Paediatr. Child Health

Infant clothing, bedding and room heating in an area of high postneonatal mortality

Paediatr. Perinat. Epidemiol.