Evidence-based risk reduction strategies known to reduce infant mortality underpin ‘Safe Sleeping’ recommendations, with key messages targeting modifiable factors which families can influence the most . This study is the first investigation of infant care practices and the uptake of public health ‘Safe Sleeping’ messages in Australia for 15 years; a period which has seen two national public health campaigns launched. Findings demonstrate inconsistencies between current recommendations and the infant sleeping practices many Queensland families employ when caring for their young infant. In this study, only 13% of families reported they routinely practised all six of the current Safe Sleep recommendations when caring for their baby.
More first-time parents responded to this survey. Decisions families make in caring for their first child will often provide the foundations for future infant care practices and sleeping behaviours employed with subsequent children [33,34,35]. Therefore, where practices differ from current guidelines, this may indicate an underestimate of practices utilised by families in the broader population.
A significantly increased risk of sudden infant death is reported for babies who are placed prone for sleep (OR: 2.3–13.1) and for babies who are placed on their side and found prone (OR: 8.7) . Despite over two decades of ‘back to sleep’ advice both nationally and internationally [12, 37, 38], non-supine sleep positioning persists with 17% of caregivers placing their infant to sleep in a prone or side sleeping position as their usual practice. However, this is less than that reported in other international studies where 26–33% reported non-supine positioning as usual infant sleep position choice [39, 40]. The dramatic reduction in SUDI incidence in the early 1990s has been directly associated with the widespread ‘Back to Sleep’ campaigns adopted at this time by many countries [2, 41, 42]. More than one-third of infants had been placed in a non-supine sleep position at some time since birth. These findings are similar to reports from other international studies (range 32–35%) [43,44,45].
Nearly 15% of families reported their infant lived in a household where at least one member of the household smoked. Maternal smoking during pregnancy was reported as 4%; this is double the rate (2%) reported in a 2013 New Zealand study . Given the self-report nature of these studies it is likely that smoke exposure is indeed higher; given the rate of maternal smoking in pregnancy in the PDC data for the target population is 12%. Under-reporting of behaviours associated with stigma is common [3, 40, 46].
Smoking has recently been described as the most important current modifiable risk factor in reducing the risk of SUDI, with a population attributable risk estimated as high as 62% . Since inception, Australia’s national public health campaigns to reduce sudden infant deaths have advised to keep baby in a smoke free environment [19, 20]. This same advice is supported globally in other international SUDI risk reduction campaigns [12, 37, 38]. It is estimated that if in-utero smoke exposure was eliminated, a third of sudden infant deaths could be prevented [47, 48]. Moreover, infants are more likely to be born prematurely and of low birth weight, further increasing infant vulnerability, when exposed to smoke during pregnancy .
Sleeping with head coverings, such as bonnets, hats, beanies and/or hooded clothing was reported as usual practice for 2% of infants, while 8% of babies had slept with head covering at some time since birth. Use of clothing and/or bedding in the sleep environment that may cover the infant’s face and/or head increases risk of airway obstruction and overheating [49, 50]. The results of two meta-analyses that examined the association between head covering and risk of SUDI suggest that over a quarter of these deaths may be prevented if the possibility of head covering was avoided [49, 50].
The advice infants be placed ‘feet-to-foot’; that is, positioning the infant with their feet to the bottom (foot-end) of the cot rather than with their head at the top or middle of the cot where they may be able to slip down under bedding contributes to recommendations in several countries [19, 20, 37]. We found 72% of Queensland families usually employ ‘feet to foot’ advice when babies are placed in a cot to sleep; slightly higher than a British population where 65% of infants were positioned ‘feet-to-foot’ .
The use of infant sleeping bags and commercially designed sleep swaddles have become increasingly popular, with 75% of families using a sleep bag or swaddle at some time. Current recommendations suggest the use of a safe infant sleeping bag removes the need for extra bedding in baby’s sleeping environment [19, 20]; loose bedding may pose a strangulation risk or cover baby’s face/head. However, care must be taken by the caregiver to ensure the sleeping bag is the correct size for the infant with well fitted neck and armholes, or sleeves (that prevents the infant slipping inside the bag), and does not have a hood . Of those families who used a sleeping bag or commercially designed sleep swaddle, 14% did not use an infant sleep bag with fitted neck and arm holes.
More than one in three families usually placed their baby to sleep in a potentially hazardous sleep environment with infants reported to have soft or bulky bedding or objects, such as pillows, doonas, quilts, sheepskins, cot bumpers, positioning devices, rolled towels/blankets or soft toys, in their sleep environment. Similar findings were reported in a New Zealand study with homemade positioning systems reported to be increasing in prevalence . Soft or bulky bedding or objects should never be placed under an infant to sleep, nor left loose in the infant’s sleeping space as they can increase the potential of suffocation, strangulation, rebreathing and entrapment [10, 36, 48]. Infants who sleep with soft bedding are reported to be at a five-fold increased risk of sudden infant death regardless of their sleep position and more than 20-fold if slept prone [48, 52].
One in four infants usually slept in a room alone for night-time sleep with nearly one in two sleeping in a room alone during the day. Studies suggest babies who sleep in a separate room to their caregiver, for both day-time and night sleeps, are at a greater risk of sudden infant death [36, 53, 54]. Sharing the same room as a caregiver permits close monitoring of the sleeping infant and allows for exchange of caregiver-infant sensory signals and cues providing protective and heightened infant arousal . SUDI occurs more frequently in unobserved sleep periods where babies are more likely to be found with bedding covering their head or found prone when they were placed on their side to sleep, compared to babies who did not die and who slept in the same room as their caregiver [53, 54]. Room sharing with an adult caregiver is reported to reduce SUDI risk by up to 50% .
One in two infants were reported to routinely sleep on sleeping surfaces for night or day sleeps that are not recommended for safe infant sleep. While cots and bassinets were the most commonly reported bed type, adult beds were the second most commonly reported sleep surface usually used for night-time sleeps, with a rocker, swing or bouncer the second most common sleep surface for day-time sleeps. Internationally, guidelines recommend infants be removed from sitting products or devices such as bouncers, car seats, prams and baby swings for sleep . Such devices are not designed as safe sleeping environments for babies; they may increase risk of airway obstruction due to chin-to-chest positioning or possible strangulation from straps .
To provide consistent messages to families, definitions for common terms relating to safe infant sleep need to be consistent. Unfortunately, this has not been the case for the terms bed-sharing and co-sleeping. These terms are often used interchangeably and are easily misconstrued. However, these terms are not synonymous. As several authors have highlighted [12, 26, 56] studies which use different criteria to define the same term create a confusing array of information that cannot easily be compared. This leads to further confusion among healthcare professionals and parents when interpreting and understanding safe sleep recommendations and the supporting evidence of such guidelines for infant sleep location. For example, co-sleeping is a term that has many definitions. It may be used to mean a sleeping arrangement where an infant sleeps on the same surface as another sleeping person [36, 57, 58]; or it may mean the infant sleeps in the same room as another without sharing a sleep surface [36, 59]; or it may mean a combination of both, that is, where the infant sleeps in close proximity (whether on the same or different surface) [36, 55]. Further confusion is added when the term bed-sharing is examined where a diverse array of definitions can be found among literature examining infant sleep location with some referring to bed-sharing as a sleeping arrangement where a caregiver and infant are both sleeping while sharing a sleep surface together , where others define it as taking baby into an sleep surface for feeding or comfort where sleeping is not necessarily intended but may occur [57, 58, 60]. Moreover, some definitions use the term co-sleeping within its definition of bed-sharing [57, 58].
The diversity and complexity of infant sleep location is truly remarkable and if confusion is highlighted among experts in the field, attention must be given to how this may be impacting practice through interpretation by families or information sharing provided by health professionals. Adherence to safe sleep recommendations increases when caregivers receive consistent messages from multiple sources with advice more likely to be followed when they understand the reasons and evidence underpinning a particular guideline [34, 61]. This consistency or lack thereof may represent a modifiable factor in promoting infant health and safe sleeping.
Even when parents do not intend to share a sleep surface with their baby it is common for parents to do so, even for short periods, with more than half of all families sharing a sleep surface when it was usually unplanned. This study found that more than one in four babies spent two or more nights a week sharing a sleep surface, with 23% sharing four or more hours. The difference between ‘planned’ care and reality is important to understand when safe sleep guidelines are developed, as recommendations should prepare parents for not only what they plan to do, but the reality of caring for a newborn. Careful consideration of the wording of public health recommendations and government policies is required when advising about infant sleep location to ensure strategies to mitigate risk in all sleep environments can be employed. Study findings are supported by observations of McKenna and McDade  who suggested infants rarely sleep in only one sleep environment, and therefore safety information for all sleeping arrangements should be provided to formulate successful public health messages. This approach acknowledges that parents may use strategies to reduce risk in circumstances where parents share a sleep surface with baby due to parenting preferences, cultural beliefs or unavoidable living circumstances, including instances where a parent may unintentionally fall asleep with a baby.
Infant mortality, specifically sleep-related infant deaths associated with suboptimal infant care practices, remains a universal priority. In a recent project to prioritise international SUDI research, Australian representatives identified ‘developing and evaluating new ways to make safe sleep campaigns more effective’ as a top research priority . Findings from the I-CARE Qld Study provide vital information for stakeholders to move forward with this goal, assisting in the translation of current guidelines into contemporary, high quality, publicly accountable services, programs and policies that meet the needs of families to continue reducing sleep-related infant mortality.
Evidence generated from this study is important and unique, as it provides infant care practice data relating to the six-key messages in Australia’s current national Safe Sleeping public health program [19, 20]. Without contextualising infant care practices within the population in which most infants develop and thrive, greater limitations are placed on our ability to develop effective public health guidelines and parent support strategies to target and assist families most vulnerable to SUDI.
Strengths and limitations
Study response rates were improved by providing reminder letters to invited families; an additional 23% (n = 762) of the final sample were received. This is an important participant recruitment strategy when planning data collection via postal invitation, particularly when intended participants are new families who have many demands for their attention. In addition, caregivers who were maternal smokers were significantly more likely to respond using the postal survey option compared to the electronic survey weblink; this has implications for future research into effective survey recruitment strategies in target populations experiencing greater vulnerability to SUDI.
Questionnaires were sent to the most comprehensive sample frame available to provide as close to a representative sample of the Queensland population as possible. However, it is unknown how those who chose to participate differ in practices to those who declined or did not respond. The demographics of participants indicates a more socially advantaged population; and as such, are more likely to be cognisant of public health messages. Therefore, results reported in this paper are likely to over-estimate the proportion of caregivers who follow safe infant sleep guidelines. Moreover, the present study was limited to one state of Australia. It would be desirable to conduct a larger national population-based study to assess prevalence differences among population groups and identify areas for targeted support nationally; especially when infant mortality is known to be higher among lower socioeconomic status groups and when Indigenous child mortality is twice the rate of non-Indigenous children .
A further limitation of this study, is the cross-sectional survey design using a self-report questionnaire, which limits infant care practices to a point in time, and subjects’ data to social desirability bias, likely providing an underestimate of less socially desirable behaviours. However, a cross-sectional design also makes such a study with a large population feasible and is consistent with reported studies that have measured infant care practices and sleeping routines within home environments for the well infant population [39, 51]. These factors, coupled with the demographics of the sample who responded may indicate an underestimate of the suboptimal practices employed by the wider community at large.
Despite these limitations, there is value in this study’s findings providing benchmarking of current practices against national recommendations; evidence for priority areas to develop and improve strategies to increase consistency of safe infant care practice; and a rationale for expanding research on infant sleep environments to more comprehensively explore the diversity and variations in infant care practices and sleep environments. Further, assessment of associations that influence family practice and the difficulties faced when implementing Safe Sleeping guidelines, along with parental decision-making processes used when deciding how they will care for and settle their infant to sleep, is required. The maternal and infant characteristics associated with suboptimal sleep routines and care practices that some families routinely employ warrants further analyses.