Intrinsic and extrinsic factors associated with night waking in 9-month-old infants

A longitudinal study of the bi-directional relations between parental bedtime and nighttime involvement and infant sleep

OBJECTIVE

This longitudinal study assessed the prospective bidirectional links between parental involvement during bedtime and nighttime and infants' sleep during the first year of life.

METHODS

The sample included 207 families at 4 months, 177 at 8 months, and 154 at 12 months. Infant sleep was assessed at home for seven nights using actigraphy, sleep diaries, and the Brief Infant Sleep Questionnaire (BISQ). Parental bedtime and nighttime involvement were reported daily by parents through sleep diaries at all time points.

RESULTS

Concomitant associations (controlling for sleeping arrangements) were found between parental bedtime and nighttime involvement and between infant objective and reported sleep quality measures (i.e., number of night-wakings, wake after sleep onset [WASO], and subjective infant sleep problems). Structural Equation Modeling analyses demonstrated significant prospective associations: Higher parental bedtime involvement at 4 months predicted an increase in infant number of night-wakings from 4 to 8 months. Moreover, higher levels of parental bedtime and nighttime involvement at 8 months predicted an increase in infant WASO from 8 to 12 months. Only one SEM model demonstrated a significant cross-lagged link from infant sleep quality to parental involvement: More perceived infant sleep problems at 4 months predicted a decrease in parental bedtime involvement from 4 to 8 months.

CONCLUSIONS

The findings suggest that higher levels of parental involvement in soothing the infant to sleep at bedtime and nighttime predict poorer infant sleep quality. Only limited evidence was found for infant-driven links.

Sleep-dependent memory consolidation in young and aged brains

Young children and aged individuals are more prone to memory loss than young adults. One probable reason is insufficient sleep-dependent memory consolidation. Sleep timing and sleep-stage duration differ between children and aged individuals compared to adults. Frequent daytime napping and fragmented sleep architecture are common in children and older individuals. Moreover, sleep-dependent oscillations that play crucial roles in long-term memory storage differ among age groups. Notably, the frontal cortex, which is important for long-term memory storage undergoes major structural changes in children and aged subjects. The similarities in sleep dynamics between children and aged subjects suggest that a deficit in sleep-dependent consolidation contributes to memory loss in both age groups.

Exploring the Relationship between Co-Sleeping, Maternal Mental Health and Expression of Complaints during Infancy, and Breastfeeding

BACKGROUND

This study explores whether the implementation of co-sleeping in infants aged 6-12 months (a) is associated with maternal complaints and mothers' difficulties regarding their infant's sleep, (b) is associated with maternal mental health, (c) affects infant sleep characteristics and maternal sleep quality, and (d) is associated with breastfeeding.

METHODS

This study is a cross-sectional study conducted from July to November 2021. A total of 151 new mothers of infants aged 6-12 months participated. All participants were divided into two different groups, the group of mothers who adopted the co-sleeping method from birth up to the time of the survey and the group of those who did not adopt co-sleeping at that time. The Brief Infant Sleep Questionnaire-Revised Short Form (BISQ-R SF), the Edinburgh Postnatal Depression Scale (EPDS), the State-Trait Anxiety Inventory (STAI), and a questionnaire on mothers' demographics were administered.

RESULTS

Regarding the mothers' complaints, mothers who co-sleep with their children have lower sleep quality than those who do not co-sleep. In respect of the mothers' mental health, there did not seem to be a statistically significant difference in the two groups. Regarding the difficulties during the sleep process, children who sleep with their parents seem to have more difficulties compared to the others (p = 0.008). It was also shown that co-sleeping children seem to have more disturbed sleep compared to those who sleep alone (p = 0.018), and a general trend obtained of a significantly higher number of awakenings for co-sleeping children (p < 0.001). Finally, breastfeeding appeared to be more related to the children of the present sample sleeping with their parents (p < 0.001).

CONCLUSIONS

This study showed that co-sleeping is associated with more difficulties in infant and maternal sleep, but no direct correlation with maternal mental health was found. In addition, it showed a positive correlation of co-sleeping with breastfeeding.

Maternal Prenatal Depressive Symptoms and Infant Sleep Problems: The Role of Infant Temperament and Sex

OBJECTIVES

We aimed to analyze whether (1) infant temperament mediates the impact of maternal prenatal depressive symptoms on infant sleep problems and (2) the mediation role of infant temperament was moderated by the infant's sex.

METHODS

The sample was comprised of 172 mother-infant dyads. Mothers completed self-reported measures of prenatal and postnatal depressive symptoms, infant temperament (negative affectivity, surgency/extraversion, and orienting regulation), and sleep problems.

RESULTS

While controlling for maternal postnatal depressive symptoms, our results revealed that (1) infant negative affectivity at two weeks partially mediated the impact of maternal prenatal depressive symptoms on sleep anxiety at six months, and (2) this mediation is independent of the infant's sex.

CONCLUSIONS

Our findings provided evidence that negative affectivity can be an early specific marker of sleep anxiety and can partially explain the negative impact of maternal prenatal depressive symptoms on further sleep problems in the infant.

Contextual considerations in infant sleep: Offering alternative interventions to families

Infant sleep problems are one of the commonly reported reasons parents seek professional help, yet what constitutes a "sleep problem" depends on the models used to explain the development of infant sleep. The current models are based on research conducted in the western context where infant solitary sleeping is the norm. Parent-child co-sleeping is the norm in many cultures around the world. We argue that the primary focus of current research on parent-child interactions as the mediating context for the development of infant sleep problems has inherently made these models and ensuing interventions less sensitive and applicable to infant sleep problems in the context of co-sleeping families. When families present for help with infant sleep difficulties, extinction based behavioral interventions or interventions focused on reducing parental presence at bedtime are commonly recommended. These recommendations may not always align with cultural values and parenting practices of all families, therefore precluding these families from getting necessary help. In attempting to provide families with choices that depart from behavioral based interventions, this paper draws on research and adapts current models to propose an alternative to conceptualize perceptions of infant sleep problems that may be sensitive to and applied across various cultural and personal contexts. We attempt to provide a rationale for interventions that are inclusive and sensitive to families where reduced parental nighttime responsiveness may not be a preferred choice.

Characterization of Parental Knowledge on Early Child Sleep and Association with Child Sleep Quality: A Cross-Sectional Pilot Study in Chongqing, China

Purpose

Parental knowledge of child sleep is typically poor, and profiling of knowledge patterns has not been performed. In recent years, the Chinese government has issued a series of administrative and legal documents to promote guidance on family education and parenting knowledge. The purpose of this study was to characterize the pattern of parental sleep knowledge for 0~3-year-old children in Chongqing, China, and to examine the associations among the knowledge pattern, guidance channel, and sleep quality.

Participants and Methods

This was a cross-sectional pilot study of 264 primary caregivers of children aged 1~36 months who completed a brief survey using the 9-item Parents' Knowledge of Child Sleep (PKCS) and a modified Chinese version of the Brief Infant Sleep Questionnaire (BISQ). Hierarchical clustering was performed to determine knowledge patterns. Logistic and multiple linear regressions were used to assess the associations.

Results

The average PKCS score was 50.2%. Parental knowledge showed a five-group pattern from I to V, with knowledge score increasing with the group number. Parents' access to sources for guidance and information on children's sleep was categorized into three categories from i to iii considering the authenticity of sources and richness of channels. Significant correlates of knowledge pattern were age (mo.) of the child (OR=0.97, p=0.019), low family income (vs high, OR=0.44, p=0.022; vs medium, OR=0.55, p=0.014), and information access patterns i and ii (vs iii with the lowest credibility and richness, OR=2.22/1.85, p=0.004/0.022). Knowledge pattern IV, with a few critical structural defects, showed a significant association with longer daytime napping (β=0.121, p<0.001).

Conclusion

The child sleep knowledge of parents in Chongqing, China, was at a low level but showed characteristic patterns. Considering the social need and policy directions, it is necessary to improve public services to provide authentic and extensive guidance to strengthen parental knowledge on child sleep in Chongqing.

Association of sleep quality with temperament among one-month-old infants in The Japan Environment and Children’s Study

This study aimed to examine the association between infant sleep quality and temperament in one-month-old infants using a large cohort study data. We used data from the Japan Environment and Children’s Study, a cohort study which follows around 100,000 women from pregnancy until their children’s development. The mothers were asked about their infants’ sleep and temperament using a structured questionnaire. Frequent crying (adjusted odds ratio [AOR]: 1.05, 95% confidence interval [CI]: 1.00–1.10) and intense crying (AOR: 1.19, 95% CI: 1.13–1.25) were positively associated with longer sleep periods during the day than at night. Female infants with longer daytime sleep periods than that at nighttime were more likely to cry frequently (AOR: 1.11, 95% CI: 1.04–1.20). Parous women with infants who had frequent night awakening believed their infants cried more intensely (AOR: 1.17, 95% CI: 1.03–1.31). The study demonstrated a specific association between sleep quality and temperament in one-month-old infants. Based on the results of this study, further sleep intervention studies are required to improve infant temperament.

Infant sleep arrangements, infant-parent sleep, and parenting during the first six months post-partum

The present study of 124 families examined linkages between patterns of sleep arrangement use across the first 6 months post-partum and (a) family socio-demographics, (b) nighttime sleep of infants, mothers, and fathers, and (c) coparenting distress, and mothers' emotional availability with infants and bedtime. Families were recruited when infants were 1-month-old, and infants were classified, from video data available at 3 and 6 months post-partum, into one of three sleep arrangement pattern groups: Solitary sleep, cosleeping, and cosleeping (at 3 months)-to-solitary sleep (at 6 months). Mothers in cosleeping arrangements were more likely to be at higher socioeconomic risk, non-White, unemployed, and to have completed fewer years of education. Controlling for these variables and for duration of breast feeding and parental depressive and anxiety symptoms, subsequent 3 (sleep arrangement pattern) X 2 (infant age: 3 and 6 months) mixed-model analyses of covariance revealed that sleep arrangement patterns were more robustly linked with maternal sleep than with infant and father sleep. Mothers in cosleeping arrangements experienced more fragmented sleep and greater variability in fragmented sleep relative to mothers of infants in solitary sleep, and fathers in cosleeping arrangements showed greater variability across the week in the number of minutes of nighttime sleep. Cosleeping was associated with mother reports of less positive and more negative coparenting, and mothers in cosleeping arrangements were independently observed to be less emotionally available with their infants at bedtime compared to mothers in the other two sleep arrangement groups. These linkages were largely upheld after statistically controlling for mothers' stated preference for sleep arrangements they were using.

Relations between infant sleep quality, physiological reactivity, and emotional reactivity to stress at 3 and 6 months

The study examines the association between infant sleep, physiological, and emotional reactivity at 3 and 6 months of age in 89 African American infants and their caregivers. Infant sleep was objectively measured at 3 and 6months using actigraphy for 7 days and nights. At 6 months of age, dyads participated in the Still-Face Paradigm (SFP) (Tronick et al., 1978) to assess infants' physiological reactivity (via respiratory sinus arrhythmia (RSA)) and emotional reactivity. Findings revealed that infant night wakings at 3 months was positively correlated with baseline RSA at 6 months (β = .35, p < .001). Night wakings at 3 months marginally predicted negative affect during the recovery episode of SFP (β = -.26, p = .057). Further, night wakings at 6-months-old predicted more positive affect during the recovery episode of SFP (β = .34, p = .007). We discuss potential explanations for these findings such as an exuberant temperament style, parenting behavior, and lack of sleep consolidation at this early age to be the focus of future studies in this area. The current study adds to the limited research examining the relationship between sleep and reactivity in the earliest months of development. Findings reveal that it is critical to take developmental timing into account as all results were unexpected in relation to the childhood literature. Moreover, this is the first study of its kind to focus on an African American sample.

Crying in the first 12 months of life: A systematic review and meta-analysis of cross-country parent-reported data and modeling of the "cry curve"

Crying is an ubiquitous communicative signal in infancy. This meta-analysis synthesizes data on parent-reported infant cry durations from 17 countries and 57 studies until infant age 12 months (N = 7580, 54% female from k = 44; majority White samples, where reported, k = 18), from studies before the end Sept. 2020. Most studies were conducted in the United States, the United Kingdom, and Canada (k = 32), and at the traditional cry "peak" (age 5-6 weeks), where the pooled estimate for cry and fuss duration was 126 mins (SD = 61), with high heterogeneity. Formal modeling of the meta-analytic data suggests that the duration of crying remains substantial in the first year of life, after an initial decline.

Reasons mothers bedshare: A review of its effects on infant behavior and development

Bedsharing is controversial for nighttime caregiving in the U.S. today, as in most of the West. However, from the standpoint of evolutionary pediatrics, anthropology, and cultural psychology, bedsharing is not controversial at all, representing the context for human infant evolution and conferring a host of physiological benefits to the infant as well as the mother. In an effort to understand the rise in Western bedsharing in recent decades (and following Ball, 2002; McKenna & Volpe, 2007), Salm Ward (2015) systematically reviewed the literature on mother-infant bedsharing and identified ten reasons why mothers choose to bedshare: (1) breastfeeding, (2) comforting for mother or infant, (3) better/more sleep for infant or parent, (4) monitoring, (5) bonding/ attachment, (6) environmental reasons, (7) crying, (8) cultural or familial traditions, (9) disagree with danger, and (10) maternal instinct. The current paper offers the "review behind the review," highlighting the scientific evidence behind the reasons mothers give for their decision to bedshare, focusing on how mothers' decisions about infant sleep location influence infant behavior and development.

Type of Milk Feeding and Introduction to Complementary Foods in Relation to Infant Sleep: A Systematic Review

Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-related decisions. This study aimed to systematically review the existing literature on infant sleep and its relation to the timing of introduction to complementary foods and type of milk feeding to better understand their role(s) in infant sleep. Cohort, longitudinal, cross-sectional studies, and controlled trials were identified using online searches of five databases up to April 2020. Twenty-one articles with a total of 6225 infants under 12 months-of-age were eligible. Exclusively breastfed infants (≤6 months-of-age) had a greater number of night wakings, but most studies (67%) reported no difference in night-time and 24 h sleep duration compared to formula-fed infants. However, after 6 months-of-age, most studies (>65%) reported breastfed infants to sleep less in the night-time and over 24 h compared to formula-fed infants. Furthermore, studies reported no association between the timing of introduction to complementary foods and infant sleep duration (<12 months-of-age). Future studies using standardized methodologies and definitions, transdisciplinary expertise, and longitudinal design are required to better understand the complex role of feeding on sleep.

Infant Sleep Difficulties at the 6th Week and the 12th Month Postpartum: What Is their Relationship with Maternal Mental Health and Other Perinatal Factors?

INTRODUCTION

Infant sleep difficulties are often a challenge for new parents and may be related to maternal mood.

AIM

The aim of this study was to investigate whether the presence of reported infant sleep difficulties at the 6th week and at the 12th month postpartum is associated with maternal psychological well-being and the presence of a mental health disorder in the perinatal period or with other perinatal factors.

METHODS

It is a retrospective longitudinal study, examining a sample of 622 women who attended a 12-month innovative psychosocial intervention. Data were obtained through the EPDS and PHQ-9 psychometric tools, and the completion of a health history. Statistical analyses included Spearman rank correlation coefficients and Chi-square tests.

RESULTS

Reported infant sleep difficulties at the 6th week postpartum were associated with a) increased maternal scores on psychometric tools (EPDS and PHQ-9) during pregnancy and at the 6th week postpartum, b) the presence of pathological maternal mental health symptoms in the perinatal period (p =.034), c) high maternal educational level (p <.001), and d) reported maternal breastfeeding difficulties at the 6th week postpartum (p =.031). Reported infant sleep difficulties at the 12th month postpartum were associated with a) increased maternal scores on the EPDS at the 6th week after birth (p =.030), and at the 6th (p =.031) and the 12th month (p =.006) postpartum, b) reported infant sleep difficulties (p <.001) and frequent infant awakenings in the puperperium (p <.001), d) maternal fatigue at the 6th week postpartum (p <.001), e) infant gastro-esophageal reflux problems (p <.001), and f) high maternal educational level (p =.001).

CONCLUSIONS

This study demonstrates a positive relationship between infant sleep difficulties at the 6th week and at the 12th months postpartum, with poor maternal mental health in the perinatal period.

Postpartum depression and mother-offspring conflict over maternal investment

BACKGROUND AND OBJECTIVES

As the mother-offspring relationship is central to human reproduction, postpartum depression symptoms are difficult to explain in evolutionary terms. We proposed that postpartum depression might arise as a result of evolutionary mother-offspring conflict over maternal investment, and investigated the association between postpartum depression symptoms, infant night waking, maternal sleep disturbance and breastfeeding frequency.

METHODOLOGY

We conducted a cross-sectional analysis using survey responses at 6 months postpartum from 1598 Finnish mothers. We hypothesized that infant night waking at 6 months postpartum would be associated with postpartum depression symptoms, and that this association would be mediated by maternal sleep disturbance and a higher breastfeeding frequency.

RESULTS

Infant night waking was moderately associated with postpartum depression symptoms, and this association was mediated by maternal sleep disturbance (R 2=0.09). Contrary to our prediction, we found that increased breastfeeding was associated with less postpartum depression symptoms.

CONCLUSIONS AND IMPLICATIONS

We conclude that postpartum depression symptoms might partly be the result of increased maternal fatigue stemming from high offspring demands on maternal investment, but that this is not due to the metabolic strain from increased breastfeeding. Studying postpartum depression from the mother-offspring conflict perspective can potentially improve our understanding of the involved behavioral processes of both mother and offspring, and allow interventions designed to benefit the well-being of both parties. Lay Summary: We proposed that postpartum depression is due to an evolutionary conflict between mother and infant, where the infant tires the mother to delay the arrival of a sibling. We found a link between infant night waking and postpartum depression, mediated by the mother's sleep, but not by breastfeeding frequency.

Infant feeding practices and sleep at 1 year of age in the nationwide ELFE cohort

Sleep problems reported by parents affect 20% to 30% of infants. Few studies focused on the longitudinal association between infant feeding practices and sleep, especially in France. Analyses were based on 8,696 infants from the French national birth cohort ELFE. Collection of feeding practices from birth to 10 months allowed for the identification of trajectories of use of baby cereals and thickened formula by group‐based trajectory modelling and calculation of duration of any breastfeeding (BF) and age at complementary feeding introduction (CFI) excluding baby cereals. Total sleep duration (TSD), night waking (NW) and sleep onset difficulties (SOD) were reported at age 1. Associations between feeding and sleep were tested by multinomial logistic regressions. BF duration ≥6 months was associated with parent‐reported frequent NW, SOD and TSD ≤ 12 h/24 h at age 1. For TSD and SOD, this association was no longer significant after accounting for parental sleep‐related practices. Early use of baby cereals (≤5 months) was associated with poor sleep. Early CFI (<4 months) was associated with shorter TSD and SOD but not NW. Early use of thickened formula (only <6 months) was related to poor sleep at age 1 (NW and SOD), whereas late (around 6 months) use of thickened formula was associated with better sleep. BF duration ≥6 months was related to poor sleep at age 1 but not after adjustment on 1‐year parental sleep‐related practices except for NW. The use of baby cereals or early CFI was not related to better sleep at age 1.

What Is “Normal” Infant Sleep? Why We Still Do Not Know

The human need for sleep is universal and unquestioned; however, humans vary in their sleep needs according to age, individual differences, as well as cultural and social norms and practices. Therefore, what is “normal” in infant sleep and the development of sleep architecture in humans is highly dependent on biological and sociocultural variables as well as socially constructed assumptions about what infant sleep “should” look like. This paper uses a multidisciplinary approach to review papers from fields including pediatrics, anthropology, psychology, medicine, and sociology to understand “normal” infant sleep. Because human culture and behavioral practice changes much more quickly than evolved human biology, and because human evolutionary history occurred in the context of breastfeeding and cosleeping, new work in the field of infant sleep architecture development would benefit from a multidisciplinary approach. To come to a consensus about what is “normal” infant sleep, researchers must agree on underlying basic assumptions of infant sleep from which to ask question and interpret findings.

Parental Cognitions About Sleep Problems in Infants: A Systematic Review

Introduction: Parental cognitions may directly and indirectly contribute to infant sleep outcomes. This review provides a systematic up-to-date overview of the associations between parental cognitions and infant sleep problems with special emphasis on temporal relationships and the content of parental cognitions. Methods: A systematic literature research in PubMed and Web of Science Core Collection sensu Liberati and PRISMA guidelines was carried out in March 2020 using the search terms (parent^* AND infant^* AND sleep^* problem^*), including studies with correlational or control group designs investigating associations between parental cognitions and sleep problems in children aged 1-6 years. Results: Twenty-three studies (published from 1985 to 2016) met inclusion criteria, of which 14 reported group differences or associations between parental sleep-related cognitions and child sleep outcomes. Nine papers additionally reported on the role of general parental child-related cognitions not directly pertaining to sleep. Findings from longitudinal studies suggest that parental cognitions often preceded child sleep problems. Cognitions pertaining to difficulties with limit-setting were especially prevalent in parents of poor sleepers and were positively associated with both subjective and objective measures of child sleep outcomes. Conclusions: Parental cognitions appear to play a pivotal role for the development and maintenance of sleep problems in young children, arguing that parents' attitudes and beliefs regarding child sleep inadvertently prompts parental behavior toward adverse sleep in offspring. Associations are however based on maternal reports and small to moderate effect sizes. Thus, additional parental factors such as mental health or self-efficacy, as well as additional offspring factors including temperamental dispositions and regulatory abilities, require consideration in further studies.

Assessment of infant sleep: how well do multiple methods compare?

The current study compares sleep variables obtained from videosomnography, actigraphy, and sleep diaries, three of the most common sleep assessment methods used in infant sleep studies. Using a sample of 90 African American 3-month olds, we compare correlations and discrepancies for seven sleep variables across each of the three pairs of assessment methods for one night of a week-long sleep study. These seven variables are indicative of sleep schedule (e.g. sleep onset time, rise time), duration (e.g. sleep period, sleep time, wake time), and fragmentation (e.g. night wakings, longest sleep period). We find that across all sleep assessment methods, correlations are highest for variables indicative of sleep schedule, and lowest for variables indicative of sleep fragmentation. Comparing the magnitude and significance of the discrepancies, we find that actigraphy and sleep diaries significantly overestimate sleep period duration and underestimate the number of night waking episodes, compared with videosomnography. Actigraphy and sleep diaries were more concordant with one another than with videosomnography. Epoch-by-epoch analyses indicated that actigraphy had low sensitivity to detect wakefulness, compared with videosomnography. Contrary to our hypothesis, the discrepancies between sleep assessment methods did not vary widely based on infant sleep location (own room vs. parent's room) or sleep surface (own bed vs. parent's bed). Limitations and implications of these findings for future research are discussed.

Considering Sleep, Mood, and Stress in a Family Context: A Preliminary Study

Background: During the first years of life, parental sleep strongly depends on child’s sleep quality. Poor parental sleep may relate to increased stress and negative mood. However, there is a lack of sleep studies focusing on all family members. This study aimed to investigate the relationship between sleep, mood, and stress in mothers, fathers and children. Methods: Data were obtained from 65 parental couples and 65 children (2 to 36 months). Data on sleep for all family members and stress of parents were completed by both mothers and fathers through questionnaires and sleep diaries. Results: Toddlers’ positive mood before nocturnal sleep was significantly associated with reduced wake times after sleep onset. Mothers reported worse sleep quality compared to fathers. Shorter sleep onset latency in fathers and better sleep efficiency in mothers were linked with better self-reported mood upon awakening. In mothers, but not in fathers, poor sleep quality was associated with higher perceived stress. Conclusion: Results suggest bidirectional relationships between sleep and mood in children, mothers and fathers. Moreover, results evidence poorer sleep in mothers, compared to fathers, which was linked with increased parenting stress. This gender gap should be further considered in studies with larger samples and in clinical contexts.

The influence of bed-sharing on infant physiology, breastfeeding and behaviour: A systematic review

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.

I. INTRODUCTION: UNDERSTANDING THE TRANSITION TO SIBLINGHOOD FROM A DEVELOPMENTAL PSYCHOPATHOLOGY AND ECOLOGICAL SYSTEMS PERSPECTIVE

The birth of an infant sibling is a common occurrence in the lives of many toddler and preschool children. Early childhood is also a time for the emergence of disruptive behavior problems that may set the stage for later problem behaviors. The current study examined individual differences in young children’s behavioral and emotional adjustment after the birth of a sibling in an effort to uncover developmental trajectories reflecting sudden and persistent change (maladaptation), adjustment and adaptation (resilience), gradual linear increases, and no change (stability and continuity). Growth mixture modeling (GMM) was conducted with a sample of 241 families expecting their second child using a longitudinal research design across the first year after the sibling’s birth (prenatal, 1, 4 8 and 12 months) on seven syndrome scales of the Child Behavior Checklist (CBCL 1.5–5:(Achenbach & Rescorla, 2000 ): aggression, attention problems, anxiety/depression, emotional reactivity, withdrawal, somatic complaints, and sleep problems. For all scales, multiple classes describing different trajectory patterns emerged that reflected predominantly intercept differences; children high on problem behavior after the birth were those high before the birth. There was no evidence of a sudden, persistent maladaptive response indicating children underwent a developmental crisis for any of the problem behaviors examined. Most children were low on all problem behaviors examined and showed little change or actually declined in problem behaviors over time, although some children did experience more pronounced changes in the borderline clinical or clinical range. Only in the case of aggressive behavior was there evidence of an Adjustment and Adaptation Response showing a sudden change (prenatal to 1 month) that subsided by 4 months, suggesting that some young children react to stressful life events but adapt quickly to these changing circumstances. Further, children’s withdrawal revealed a curvilinear, quadratic path, suggesting children both increased and decreased in their withdrawal over time. Guided by a developmental ecological systems framework, we employed data mining procedures to uncover the child, parent, and family variables that best discriminated the different trajectory classes and found that children’s temperament, coparenting, parental self-efficacy, and parent-child attachment relationships were prominent in predicting children’s adjustment after the birth of an infant sibling. Finally, when trajectory classes were used to predict sibling relationship quality at 12 months, children high on aggression, attention problems, and emotional reactivity in the year after the birth engaged in more conflict and less positive involvement with the infant sibling at the end of the first year.

Sleep location and parent-perceived sleep outcomes in older infants

OBJECTIVES

Initial studies indicate more independent and consolidated sleep in the first few months in infants who sleep separately. Little is known, however, about the relationship of sleep location (separate room, room-sharing, bed-sharing) with sleep outcomes in older infants (ages 6-12 months). It was expected that those who sleep in a separate room would have better parent-perceived sleep outcomes and more positive sleep health behaviors.

METHODS

Parents of 6236 infants (6-12 months) in the United States (US) and 3798 in an international sample (Australia, Brazil, Canada, Great Britain, and New Zealand) completed a smartphone app-based expanded version of the validated Brief Infant Sleep Questionnaire.

RESULTS

A total of 37.2% of the infants in the US and 48.4% in the international sample slept in a separate room. In both samples, infants who slept in a separate room as opposed to room-sharing or bed-sharing had parent-perceived sleep outcomes and sleep-related behaviors that reflected earlier bedtimes, shorter time to fall asleep, more nighttime and total sleep, and increased sleep consolidation. They were also more likely to have a consistent bedtime routine and to fall asleep independently, as well as less likely to feed to sleep at bedtime and during the night. In addition, parents of separate room sleepers perceived bedtime to be less difficult and sleep to be better overall.

CONCLUSIONS

Overall, 6- to 12-month-old infants who slept in a separate room had better reported sleep outcomes and fewer parent-perceived disturbances at bedtime than infants who room-shared with their parents, as well compared to those who slept in their parents' bed.

A Developmental Cascade Model of Behavioral Sleep Problems and Emotional and Attentional Self-Regulation Across Early Childhood

This article documents the longitudinal and reciprocal relations among behavioral sleep problems and emotional and attentional self-regulation in a population sample of 4,109 children participating in Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC)-Infant Cohort. Maternal reports of children's sleep problems and self-regulation were collected at five time-points from infancy to 8-9 years of age. Longitudinal structural equation modeling supported a developmental cascade model in which sleep problems have a persistent negative effect on emotional regulation, which in turn contributes to ongoing sleep problems and poorer attentional regulation in children over time. Findings suggest that sleep behaviors are a key target for interventions that aim to improve children's self-regulatory capacities.

Sleep arrangements, parent-infant sleep during the first year, and family functioning

The present longitudinal study addressed the ongoing debate regarding the benefits and risks of infant-parent cosleeping by examining associations between sleep arrangement patterns across the first year of life and infant and parent sleep, marital and family functioning, and quality of mothers' behavior with infants at bedtime. Patterns of infant sleep arrangements across the infants' first year were derived from information obtained from 139 families at 1, 3, 6, 9, and 12 months of infant age in a central Pennsylvania sample. Linkages between these patterns and parent-infant sleep, marital and coparenting stress, and maternal behavior at bedtime (from video-recordings) were assessed. Compared with families whose infants were solitary sleepers by 6 months, persistent cosleeping was associated with sleep disruption in mothers but not in infants, although mothers in persistent cosleeping arrangements reported that their infants had more frequent night awakenings. Persistent cosleeping was also associated with mother reports of marital and coparenting distress, and lower maternal emotional availability with infants at bedtime (from home observations). Persistent cosleeping appeared to be a marker of, though not necessarily a cause of, heightened family stress, although the present design did not enable strong tests of causal processes, and results may be particular to cultures that are not supportive of cosleeping. Findings are discussed in terms of cultural contexts of infant sleep and the need for further investigations into the role of the health of the family system in influencing how parents structure infant sleep. (PsycINFO Database Record

Parental Involvement in Infant Sleep Routines Predicts Differential Sleep Patterns in Children With and Without Anxiety Disorders

This study compared parents' retrospective reports of their involvement in infant settling strategies and their relation to current sleep patterns among children (N = 84, ages 7-11) with generalized anxiety disorder (GAD) and healthy controls. Parents of children with GAD were significantly more likely to report rocking their infants to sleep and putting infants down when they were already asleep than parents of healthy controls, even when accounting for infant health-related factors and parental anxiety. Greater involvement in infant sleep routines also predicted sleep patterns (measured via actigraphy) during childhood, though opposite relationships were observed in the two groups. Early involvement was related to poorer sleep in control children but better sleep for children with GAD even after controlling for current parenting practices. Findings suggest differential effects of early sleep-related parenting for children with and without later anxiety disorders with possible implications for early intervention.

Bidirectional associations between bedtime parenting and infant sleep: Parenting quality, parenting practices, and their interaction

In keeping with transactional conceptualizations of infant sleep development (Sadeh, Tikotzky, & Scher, 2010), the present study was an examination of longitudinal, bidirectional linkages between bedtime parenting (through direct observations of parenting practices and quality) and infant sleep across the first 6 months postpartum. In doing so, we also drew from Darling and Steinberg's (1993) conceptual model to examine parenting quality as a moderator of linkages between specific bedtime practices and infant sleep. Multilevel model analyses revealed that the strongest increases in infant nighttime sleep across the first 6 months occurred among infants of mothers who engaged in low levels of nursing at bedtime. Within-person linkages between mothers' emotional availability (EA) at bedtime, infant distress, and infant sleep were found, such that at time points when mothers were more emotionally available, infants were less distressed and slept more throughout the night. Several moderating effects of maternal EA on linkages between parenting practices and infant sleep were obtained that were consistent with predictions from Darling and Steinberg (1993). Higher maternal EA in combination with less close contact at bedtime was associated with more infant sleep across the night on average, and higher EA in combination with fewer arousing bedtime activities predicted more rapid increases in infant sleep with age. Finally, there was evidence of infant-driven effects, as higher infant nighttime distress predicted lower EA at subsequent time points. Results showcased the complex, reciprocal interplay between parents and infants in the development of infant sleep patterns and parenting behavior during the first 6 months postpartum. (PsycINFO Database Record

Parent-child bed-sharing: The good, the bad, and the burden of evidence

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.

Infant sleep and night feeding patterns during later infancy: association with breastfeeding frequency, daytime complementary food intake, and infant weight

Infant sleep is a common concern for new parents. Although many expect a newborn infant to wake frequently, encouraging a baby to sleep through the night by a few months of age is seen as both a developmental aim and a parenting success. Many new mothers believe that their infants' diet is related to their sleep; formula milk or increased levels of solid food are often given in an attempt to promote sleep. However, the impact of these in later infancy is not understood. In the current study 715 mothers with an infant 6-12 months of age reported their infants' typical night wakings and night feeds alongside any breastfeeding and frequency of solid meals. Of infants in this age range, 78.6% still regularly woke at least once a night, with 61.4% receiving one or more milk feeds. Both night wakings and night feeds decreased with age. No difference in night wakings or night feeds was found between mothers who were currently breastfeeding or formula feeding. However, infants who received more milk or solid feeds during the day were less likely to feed at night but not less likely to wake. The findings have important implications for health professionals who support new mothers with infant sleep and diet in the first year. Increasing infant calories during the day may therefore reduce the likelihood of night feeding but will not reduce the need for parents to attend to the infant in the night. Breastfeeding has no impact on infant sleep in the second 6 months postpartum.

Associations between infant temperament, maternal stress, and infants' sleep across the first year of life

Effects of temperament and maternal stress on infant sleep behaviors were explored longitudinally. Negative temperament was associated with sleep problems, and with longer sleep latency and night wakefulness, whereas maternal stress was associated with day sleep duration, suggesting infant and maternal characteristics affect sleep differentially.

Translating research-based knowledge about infant sleep into practice

PURPOSE

Review infant sleep research with a focus on understanding the elements related to infant safety and infant and maternal well-being during nighttime care.

DATA SOURCES

This review summarizes current research and addresses the controversies and conflicting outcomes reported in infant nighttime care. This review addresses current literature on infant sleep patterns, as well as factors that influence infant sleep and are consequences of different care routines. Conversation points are provided to help nurse practitioners (NPs) address safety and practice concerns.

CONCLUSIONS

Shared information can help parents provide a safe and healthy environment for infants and help to facilitate communication ties between the healthcare providers and the families.

IMPLICATIONS FOR PRACTICE

NPs need to help parents understand infant sleep patterns norms, what is current knowledge about infant nightwakings and parental presence, as well as about approaches to altering infant sleep patterns. Integrating this knowledge with parent preferences that are influenced by cultural practices and individual differences is crucial in helping parents develop a strong sense of competence and comfort with their choices and behaviors.

Troubled sleep: Night waking, breastfeeding and parent-offspring conflict

Disrupted sleep is probably the most common complaint of parents with a new baby. Night waking increases in the second half of the first year of infant life and is more pronounced for breastfed infants. Sleep-related phenotypes of infants with Prader-Willi and Angelman syndromes suggest that imprinted genes of paternal origin promote greater wakefulness whereas imprinted genes of maternal origin favor more consolidated sleep. All these observations are consistent with a hypothesis that waking at night to suckle is an adaptation of infants to extend their mothers’ lactational amenorrhea, thus delaying the birth of a younger sib and enhancing infant survival.