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Several Australian studies have provided data on infant sleep with results indicating that 32% (Lam et al., 2003), 34% (Bayer, et al., 2007) and 46% (Hiscock & Wake, 2001) of mothers experience difficulty with settling their infant to sleep at bedtime and following a night awakening. Infant sleep problems, which can be

experienced by parents as disruptive and distressing (Bayer et al., 2007) are one of the most frequent problems parents discuss with paediatricians and other allied health professionals (Adams et al., 2004). While the prevalence of infant sleep problems in Australia is broadly similar to that reported in overseas studies, research is needed to better understand the factors that contribute to sleep disturbance in Australian infants.

The causes of infant sleep disturbance are not well understood. As is evidenced from the literature review, most previous studies have examined individual predictors or particular categories of predictors of infant sleep problems. Few studies have evaluated models of infant sleep based on factors considered important to infant sleep outcome. It has been suggested that conceptual models of infant sleep (Morrell & Steele, 2003; Sadeh & Anders, 1993; Tikotzky & Sadeh, 2009) be developed to fully understand the multiple complex processes associated with infant sleep outcome. Notably, with few exceptions (Mindell, Sadeh, Kohyama, et al., 2010) the majority of studies have tended to focus on predictors of infant sleep disturbance rather than viewing infant sleep outcome as a continuum.

One area that has received wide research attention is the link between the maternal behaviour of active physical comforting and infant sleep outcome. Most

studies that have examined the variety of behaviours that mothers use to settle their infants to sleep have been conducted in countries outside Australia. Little is known, however, about the behaviours Australian mothers use to settle their infants to sleep and the link between active physical comforting and infant sleep outcome has not been examined in Australian infants.

As described in the above literature review, in the last decade research attention has been directed towards understanding the reasons that lead some mothers to become more actively involved in settling their infants to sleep at night and others to limit involvement. It has been proposed that the specific cognitions regarding setting limits, anger towards the infant and doubt about parenting, that a mother holds about her infant’s sleep may influence the type and amount of involvement she has with her child at bedtime (Tikotzky & Sadeh, 2009). While there is large body of evidence suggesting that the influence parental cognitions have on child behaviour is mediated by the way parents behave and react towards their children (Bugental & Johnston, 2000), only a few studies, and none from Australia, have examined the links between maternal cognitions, maternal comforting strategies and infant sleep outcome.

Despite the links that have been shown between maternal cognitions and the type and amount of parental involvement at bedtime and following a night awakening (Morrell, 1999b; Sadeh et al., 2007; Tikotzky & Sadeh, 2009) there has been only limited attention given to understanding the past and current experiences that influence maternal cognitions and therefore maternal bedtime behaviours.

The influence of mothers’ perceptions of being parented in childhood may affect the quality of a mother’s parenting behaviour including that related to bedtime settling strategies. There are theoretical assumptions from attachment theory (Bowlby, 1969) which suggest that a mother’s internalised childhood experiences will affect the way she parents her child. In particular her beliefs and expectations about infant sleep may be influenced by her perception of the parenting she received (Benhamou, 2000). Few studies, however, have examined the contribution of recalled experience of being parented to infant sleep outcome and none of these studies have been conducted in Australia.

Findings presented above indicate that numerous studies have demonstrated strong links between mothers’ perceptions of being parented in childhood and

depression and trait anxiety in adulthood. As many of these studies have been conducted with clinical populations (Gerlsma et al., 1990), less is known about the relationship between early parenting history and mood in non-clinical populations. Further, while maternal depression and to a lesser extent, trait anxiety have been consistently linked to infant sleep outcome, almost no research attention has been given to exploring the links between perceptions of being parented in childhood, maternal mood and infant sleep outcome. No studies in Australia have assessed the influence of a mother’s own parenting history on her current well-being and how this influences the strategies the mother uses to settle her infant at bedtime.

As is evidenced in the literature review, maternal sleep quality has been the focus of research during pregnancy and/or the postpartum period (Lee et al., 2000; Swanson et al., 2011) and fragmented maternal sleep has been shown to be linked to

problematic infant sleep (Fisher et al., 2002). Few studies, however, and none from Australia, have explored how women’s sleeping patterns prior to pregnancy may affect infant sleep outcome. As previously noted (2003), there is a danger that women’s complaints of poor quality sleep during pregnancy may mask the long-standing nature of their sleep difficulties.

Given the well-established body of literature on adult insomnia showing a high familial incidence, with mothers particularly implicated, and evidence for the

persistence of early sleep problems into childhood and adulthood, it seems important to investigate how a mother’s own sleep history may shape her expectations and parenting behaviour regarding her infant’s sleep.

This study has therefore been designed to both explore factors that contribute to infant sleep outcome and to increase our knowledge of how maternal cognitions

influence maternal-infant bedtime interactions and hence infant sleep patterns based on maternal report. The consideration of the factors that are associated with such

cognitions has been a notable gap in the literature. Previous studies exploring the link between maternal factors and infant sleep have predominantly looked at factors

predictive of infant sleep disturbance/problems. This study has taken a broader approach and attempted to explore the influence of maternal factors on infant sleep outcome. In addition, the majority of studies exploring infant sleep have recruited either multiparous women or samples of mixed parity. In an attempt to limit the influence of confounding variables, all participants in this study were first-time mothers.

2.2 Aims

The primary aim of the current study was to assess the relative contribution of maternal factors, including perception of past parenting received, current maternal psychological functioning, sleep history, and night settling behaviour to infant sleep outcome in a sample of mothers with infants aged 6 to 9 months. A further aim was to investigate the extent to which these variables affect infant sleep through their link to maternal cognitions. Figure 1 presents a conceptual model of infant sleep outcome that was developed to address these aims.