Sleep patterns of co-sleeping and solitary sleeping infants and mothers: a longitudinal study

Sleep initiation patterns and sleep quality among toddlers in the southeast of China: initial study results

BACKGROUND

A large number of psychological consequences including sleep health emerged during the 2019 Coronavirus disease (COVID-19) pandemic. Sleep patterns in toddlers are vulnerable to negative environmental exposures, however, very few studies on this topic have been published so far.

OBJECTIVES

In this paper, we aimed to investigate the sleep patterns and associated factors in toddlers from China confined at home in the context of COVID-19 pandemic.

METHODS

From April to November 2021, a convenience sample of 493 parents of young children aged (12-35 months) were surveyed from Fuzhou, Sanming, Quanzhou, Nanping, and Longyan cities in the Fujian Province, China. A cross-sectional survey was conducted via Electronic questionnaires to collect parent and child social-demographic characteristics. The Brief Infant Sleep Questionnaire (BISQ) was used to collect data on sleep practices, sleep duration and patterns, as well as the number of nocturnal awaking .

RESULTS

The mean age of toddlers was 2.11 years old, and 52.54% (259/493) were males. Among the 493 toddlers' sleep patterns, 331(67.1%) initiated sleep accompanied by parents, 67(13.6%) slept independently, 59 (12.0%) were breast fed/bottle fed to initiate sleep, 27 (5.5%) were held and 9 (1.8%) rocked. The clear longitudinal association between the duration of night-time sleep, the frequency of nighttime awakenings, and various sleep patterns remains clear (p < 0.05). Multiple linear regression analysis indicated that sleep initiation with bottle-feeding/breast-feeding and rocked significantly increased the frequency of nighttime awakenings and reduced the duration of nighttime sleep (p < 0.05), as held was dramatically only for increasing the number of nighttime awakenings (p < 0.05). Multi-variate logistic regression analysis demonstrated that toddlers with severe sleep difficulties had a higher probability of being rocked to initiate sleep (p < 0.05). Conversely, young children with minor sleep problems were more apt to be in bed alone to initiate sleep (p < 0.05).

CONCLUSIONS

During the COVID-19 pandemic, most infants and toddlers initiated sleep accompanied by parents and tend to have electronic media exposure before bedtime. Increased waking at night may be associated with sleep initiation with breast-feeding/bottle-feeding. Therefore, pediatric practitioners in primary community hospitals should pay attention to the education and promotion of sleep hygiene and parenting knowledge of young children to avoid the formation of poor sleep hygiene habits.

Infant Safe Sleep in the District of Columbia: Better for Both

Sudden unexpected infant death (SUID) rates within the District of Columbia (DC) vary, with rates 3 times higher in certain geographical areas than the cumulative rate in DC and 7 times higher than the national rate. The majority SUIDs are due to unsafe sleep practices. Although safe sleep education and resources are available in these areas, the high sleep-related infant mortality suggests unmet barriers to infant safe sleep. We sought to investigate potential contributions to local infant mortality through focus groups regarding infant sleep practices among DC caregivers. In this qualitative study, caregivers were probed regarding barriers and facilitators of infant sleep practices. Data were collected until thematic saturation was reached, then coded. Themes were developed and revised in an iterative manner. Fifteen caregivers participated in three focus groups. Themes included sources of infant sleep knowledge, challenges for infant sleep, and motivators for infant sleep choice. All caregivers reported knowledge of safe sleep practices. Infant sleep practices varied, and included unsafe practices such as bed sharing, co-sleeping, and use of swings or bouncers for infant sleep. Challenges of adhering to safe sleep practices included infant needs, competing family demands, the overwhelming nature of newborn sleep, threats, and conflicting information. Motivators for infant sleep practices included better sleep, convenience, safety, tradition, and needs of the infant and caregiver. Although caregivers report knowledge of safe sleep recommendations, actual infant sleep practices vary and include unsafe sleep practices. More focused interventions are needed to address this gap between safe sleep knowledge and practice.

From co-regulation to self-regulation: Maternal soothing strategies and self-efficacy in relation to maternal reports of infant regulation at 3 and 7 months

This study, conducted in Germany, examines the role of maternal soothing strategies to explain the association of maternal self-efficacy with infant regulation (crying and sleeping behavior). Questionnaire data of 150 mothers, living in Germany, with mixed ethnic and educational backgrounds were collected when infants were 3 and 7 months old. Two types of maternal soothing strategies were distinguished: close soothing, involving close physical and emotional contact, and distant soothing, involving physical and emotional distancing from the infant. A cross-sectional SEM at 3 months indicated that maternal self-efficacy is associated with reported infant regulation through distant soothing strategies. Low maternal self-efficacy was associated with frequent maternal use of distant soothing, which in turn was related to reported infant regulation problems, that is, non-soothability and greater crying frequency. Frequent use of close soothing was associated with reported infant sleeping behavior, that is, frequent night-time awakenings. A longitudinal SEM further indicated that the effects of close soothing persisted at least until the infants' age of 7 months. The study showed how low maternal self-efficacy, increased use of distant soothing, and reported early infant regulation problems are intertwined and that, due to their persisting positive effect on infant soothability, close soothing better supports infant development.

Concordance in parent-child and sibling actigraphy-measured sleep: Evidence among early adolescent twins and primary caregivers

STUDY OBJECTIVES

Growing evidence suggests concordance between parent and youth sleep. However, no known study has simultaneously examined concordance among siblings' sleep patterns. This study investigated daily and average concordance in (1) parent-youth and (2) sibling actigraphy-measured sleep, as well as the degree to which sibling concordance varied by sleeping arrangements.

METHODS

516 twin siblings (Mage = 10.74, 51% female; 30% monozygotic (MZ) twin pairs, 37% same-sex dizygotic pairs (DZ-ss), 33% opposite-sex DZ pairs (DZ-os)) and their primary caregivers (Mage = 40.59, 95% female) wore wrist-based accelerometers for 7 consecutive nights to measure sleep duration, efficiency, midpoint time, and latency. Primary caregivers also reported on demographics, youth pubertal status, and room-sharing. Two-level multilevel models were estimated to examine daily and average concordance in parent-youth and sibling sleep.

RESULTS

Daily concordance was observed between parent and youth sleep duration and midpoint; average concordance was found for sleep duration, midpoint, and latency. Within sibling dyads, daily and average concordance was evident across all sleep parameters (duration, efficiency, midpoint, latency), with generally stronger concordance patterns for MZ than DZ twin pairs, and for twins who shared a room with their co-twin.

CONCLUSIONS

This is the first known study to document concordance among parent-youth and siblings' actigraphy-measured sleep within the same study (i.e., triad). Our findings can help inform the development of family-level interventions targeting daily and overall sleep hygiene.

Does the feeding method affect the quality of infant and maternal sleep? A systematic review

Breastfeeding brings many benefits to both mother and infant. Although, many women stop breastfeeding their infants too soon. The perceived association between breastfeeding and sleep may influence their decision to terminate breastfeeding. In our systematic review, we focused on mapping the relationship between infant feeding method and total sleep time (TST), number of nocturnal awakenings, awakenings after sleep onset (WASO) of mothers and infants and sleep quality of mothers. We searched four databases according to selected keywords and inclusion criteria - articles published in peer-reviewed journals between 2012 and 2022; English language; a sample consisting of mothers, infants, or both (without psychiatric and health problems); a comparison of the sleep quality of breastfed and formula-fed children or breastfeeding and formula-fed mothers. We read 260 full texts of selected articles. A total of 35 articles were included in this review. Due to significant heterogeneity, meta-analysis was not possible to accomplish. The results are processed according to narrative synthesis. Most studies agree that breastfed infants wake up more often at night. Total sleep time and time spent awake during the night (WASO) did not differ between breastfed and non-breastfed infants. We observed identical results in sleep variables among mothers. Additionally, there was no difference in maternal sleep quality. The synthesis revealed that the results may have differed due to using subjective, objective methods or the infant's age. It is important to remember that night waking is a more complex concept. Infants wake for many reasons, not just due to breastfeeding. The narrative synthesis indicated that the chosen study design, measurement method, the variables, and the infant's age could influence outcomes. In addition, other variables appeared that may affect the entire process. Therefore, we recommend that attention be paid to this in future studies.

Pre- and postnatal safe sleep knowledge and planned as compared to actual infant sleep practices

BACKGROUND

Our objectives were to compare safe sleep knowledge, attitudes and planned vs. actual infant sleep practices among expectant mothers before and after their infant's birth and to determine whether differences (if present) were associated with any demographic variables.

METHODS

Study participants were surveyed at their 28-week prenatal and 6-week postpartum obstetric clinic visits from November 2019-February 2021. Due to COVID-19 pandemic cancellation of in-person postpartum visits, many participants received text messaging encouraging them to take the follow-up survey online. Frequency and comparative analyses were performed.

RESULTS

355 women (44%) completed both pre- and postnatal surveys. Many participants increased their safe sleep knowledge during the study. For example, of those who were unsure or thought it safe for a baby to sleep in a baby swing/bouncy seat, two-thirds (67/102, 66%) stated it was unsafe on the postnatal survey. In addition, many who were unsure or planned sleep practices considered unsafe prenatally reported utilizing safe sleep practices on their postnatal survey. For example, of those unsure or planning to use a crib bumper (17% of the total), almost all (88%) were not using one postnatally. Conversely, some participants who reported they would be following safe sleep practices prenatally were not doing so postpartum. For example, 13% of those stating they would place their child on their back reported using another sleep position on the postnatal survey. Certain demographics had higher proportions reporting this reversal for specific safe sleep practices. For example, non-Hispanic Whites (19%) as compared to other races/ethnicities (5%) and those with incomes ≥ $75,000 (21%) as compared with those with less income (9%) had higher proportions stating their infant would sleep in the same room but then reported postnatally they were sleeping in a different room, p = 0.0094 and p = 0.0138, respectively.

CONCLUSIONS

We observed increases in safe sleep knowledge and that some participants followed safer sleep practices than they had planned. However, there were also participants who planned to use safe sleep practices prenatally who were not doing so after their baby's birth. Our study identified demographics for which targeted safe sleep education and more effective interventions may be needed.

Parenting in place: Young children's living arrangement and migrants' sleep health in South Africa

Migration research tends to treat childrearing as a secondary role for migrants. By prioritising the economic objectives of migration, most models present migrants as either delaying childbearing or, if they have young children, not living with them. However, migration has become increasingly feminised, the types of mobility more varied, while the returns to migration remain uncertain at best. At the same time, norms around childrearing are shifting, and the capacity of kin to take care of children may be weakening. In such contexts, migrants may not want to or be able to be separated from their children. Confronting such difficult decisions and their consequences may be reflected in poor sleep health for the migrant parent. We draw on data from the Migration and Health Follow-Up Study (MHFUS) in South Africa to examine the following questions: (i) To what extent is children's coresidence associated with sleep health for migrant parents? (ii) Do effects vary by sex of migrant? and (iii) Do effects vary by location of migrant? Results from propensity score matching confirm that migrants who coreside with all their young children are more likely to experience healthy sleep compared to those who have nonresident or no young children. However, stratified analysis shows that these effects are only significant for women and those not living in Gauteng province. The value of these findings is underscored by the need for research on the well-being of migrant parents who are negotiating multiple agendas in economically precarious and physically insecure destinations.

How do infant feeding method, sleeping location, and postpartum depression interact with maternal sleep quality?

New mothers generally experience poor and/or disrupted sleep. A range of infant care and mental health factors may impact new mothers' sleep quality. A cross-sectional online survey was completed by a sample of 101 Australian new mothers with children under 12 months (M = 5.52 months, SD = 3.29 months) to examine the relationship between infant feeding method, infant sleeping location, and postpartum depression with maternal sleep quality. Subjective maternal sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI), and postpartum depression was measured using the Edinburgh Postpartum Depression Scale (EPDS). Overall, new mothers experienced poor subjective sleep quality, with high average PSQI scores, above the cut-off of 5 (M = 9.63, SD = 4.07). The majority of new mothers did not experience postpartum depression, with an average EPDS score below the cut-off of 11 (8.66, SD = 5.20). Mothers who breastfed their infants experienced significantly better subjective sleep quality than mothers who bottle-fed, with a medium effect size (ηp2 = 0.458). Subjective maternal sleep quality did not differ based on infant sleeping location. Poor subjective maternal sleep quality was a significant predictor of postpartum depression. While poor sleep was common in this sample of Australian new mothers, this study demonstrated that new mothers who breastfeed may experience slightly better subjective sleep quality than other feeding methods. Further research into, and better services for the education and advocation of, new mothers' sleep quality will be beneficial to both new mothers and clinicians.

Concordance of objective and subjective measures of sleep in children with neurodevelopmental conditions: A systematic review and meta-analysis

The purpose of this systematic review and meta-analysis is to delineate the concordance of objective and subjective measures of sleep in children with neurodevelopmental conditions (NDCs). A systematic literature search identified 31 studies that compare objective and subjective estimates of sleep parameters in autism, ADHD or rare genetic syndromes associated with intellectual disability. The meta-analyses revealed smaller mean differences and larger correlations indicative of greater concordance for parameters associated with sleep scheduling compared to parameters associated with sleep duration and night awakenings. Relative to objective measures, subjective measures produced: 1) greater estimates of total sleep time, sleep efficiency and time in bed; and 2) lower estimates of wake after sleep onset and number of night awakenings. Subgroup analyses also revealed differences in concordance between measurement comparison types (e.g., stronger correlations between actigraphy and sleep diaries, compared to actigraphy and questionnaires) and NDC diagnostic groups. The results predominantly replicate concordance trends observed in typically-developing samples, although some NDC-specific patterns of concordance were identified. This indicates that objective and subjective sleep measures retain broadly similar properties across populations, although researchers and clinicians should be cautious of the impact of NDC-related characteristics on sleep parameter estimates. These findings should inform sleep assessment design and the interpretation of sleep parameter estimates in NDCs, increasing the rigour of sleep parameter description across research and clinical settings.

Sleeping Like a Baby: An Investigation of Bed-Sharing, Co-Sleeping, and Breastfeeding Among Pregnant Adults During the COVID-19 Pandemic

Introduction: Given the lack of clarity in the literature related to the impact of breastfeeding intentions on sleeping practices, the current research aimed to investigate the relationship between co-sleeping or bed-sharing and breastfeeding intentions among a sample of pregnant adults, during the coronavirus disease 2019 (COVID-19) pandemic. Materials and Methods: Pregnant adults from a large nationally representative sample, responded to a one-time, online Qualtrics survey between October and November 2020. Pregnant adults (n = 544) were asked closed and open-ended questions about their family characteristics, sociodemographic factors, sleeping and breastfeeding habits, and intentions. This protocol was approved by the Wesleyan University Institutional Review Board. Results: Bed-sharing (odds ratio [OR] = 2.47) and co-sleeping (OR = 3.52) intentions doubled and tripled, respectively, intentions to breastfeed at 3 months. Additionally, income at some higher levels (i.e., $150,000+/year) significantly increased breastfeeding intentions at 3 months compared with the lowest income category (OR = 5.74, p = 0.011). There was also a significant relationship between intentions to bed-share (OR = 2.96, p = 0.012) and co-sleep (OR = 3.62, p < 0.001) with breastfeeding at 6 months. Prior breastfeeding experience was significantly associated with breastfeeding intention at 6 months (OR = 1.88, p = 0.035). Based on the qualitative findings, breastfeeding ease was by far the most common motivation for co-sleeping or bed-sharing, followed by security/safety, closeness, and past experience. Conclusion: Plans to bed-share and co-sleep, significantly increased the odds of breastfeeding intentions up to 6 months postpartum. Supporting breastfeeding should include conversations about parent-infant sleeping modality, style, and preference. Future research is necessary to understand the directional impacts of these decisions and the predictive role of prenatal intentions on postpartum behaviors in this context.

Possible contribution of better maternal psychological well-being to the acquisition of sleeping through the night in infants during the early postpartum period

The objective of this study was to elucidate whether better maternal psychological well-being contributes to the acquisition of "sleeping through the night" (STN) in infants during the early postpartum period. Fifty-two primiparous mothers completed the General Health Questionnaire-28 (GHQ-28) in the third trimester (prenatal) and when the conceptional ages of their babies reached 8-9 weeks (hereafter, 2 months), 12-13 weeks (3 months), and 16-17 weeks (4 months). They also recorded babies' nocturnal sleep patterns in a timetable for 5 consecutive days each month postpartum. "Regular STN" was defined when the mean of longest nocturnal sleep duration for 5 consecutive days was > 8 h or between 6 and 8 h with < 1.0 nocturnal awakenings. According to these criteria, a total of 14 infants (27 %) acquired regular STN at 4 months (referred to as "STN infants"), with STN infants showing a marked increase in longest nocturnal sleep duration and a decrease in nocturnal awakenings from 2 to 3 months of age. The mothers of STN infants demonstrated steady reductions in postnatal GHQ-28 scores and had significantly lower prenatal GHQ-28 scores compared with the mothers of non-STN infants (3.7 ± 3.0 vs. 6.4 ± 4.1, p = 0.027). In random forest models for binomial classification, both prenatal and postnatal (at 4 months) GHQ-28 scores were identified as significant covariates for distinguishing STN infants, and other important covariates, including weeks of delivery, stepfamily, birth weight of the infant, and maternal co-sleeping at bedtime, were selected. Among these covariates, maternal co-sleeping at bedtime had relatively stronger correlations with both STN infants (r = - 0.440) and prenatal maternal GHQ-28 scores (r = 0.377). In conclusion, because prenatal maternal psychological well-being was thought to predict the acquisition of STN in infants, infants born from mothers with better psychological well-being appear to have some advantages in acquiring STN. These cross-lagged correlations suggest that the pathway from mothers to infants may be mediated by certain parenting behaviors, such as maternal co-sleeping at bedtime.

Can cry tolerance be increased in mothers of infants with sleep problems, and why does it matter? A quasi-experimental study

STUDY OBJECTIVES

Infant sleep problems are one of the most common complaints of new parents. Research to date has demonstrated a relationship between low parental cry tolerance and infant sleep problems. The aim of this study was to explore whether three emotion regulation strategies could increase parental cry tolerance.

METHODS

This study utilised a quasi-experimental design. We recruited 83 females (Mage= 32, SD= 5.26) comprising 3 groups: mothers of good sleeping infants aged 6-24 months, mothers of poor sleeping infants aged 6-24 months, and good sleeping women aged 23-40 years without children. Participants were instructed to listen to crying audio segments and indicate when they felt the child needed to be tended to (measured in seconds). This crying audio was paired with one of three emotion-regulation strategies (i.e., music, gaming, reappraisal). Each participant completed all 4 cry conditions which were counterbalanced to control for order effects.

RESULTS

We found that all three strategies yielded significantly longer reaction times (indicating higher cry tolerance) compared to the control condition (p <.001). We also found that mothers of poor sleepers and good sleeping women benefitted from all three emotion regulation strategies compared to control (p <.001 and p= <.05, respectively). The cry tolerance of mothers of good sleepers, on the other hand, did not differ between the control condition and any of the strategies (all ps >.05).

CONCLUSIONS

This demonstrates that cry tolerance can be increased using emotion regulation strategies, such as distraction via music or gaming, and reappraisal. This has clinical implications for families implementing behavioural sleep interventions.

Associations between demographic and parental factors and infant sleep characteristics

Although sleep problems are highly prevalent in infants, the intrinsic and extrinsic factors that influence sleep consolidation and regulation in this age group are not well understood. This study aimed to examine the cross-sectional associations of demographic and parental factors with infant sleep characteristics. Participants were 97 Canadian mother-infant dyads primarily from Edmonton, Alberta. Demographic factors (e.g., infant age), parenting practices (e.g., sleep position, sleep initiation methods), and infants sleep characteristics (e.g., the frequency of nighttime awakenings) were assessed using the Brief Infant Sleep Questionnaire. Maternal sleep characteristics (e.g., nighttime sleep duration) were assessed using Actigraph accelerometers. Infant age (mean = 4.24 ± 2.90) was associated with most infant sleep characteristics. In multiple regression models for infant nighttime sleep duration, after removing influential observations, a negative association for side (vs. prone) sleep position was, respectively, observed. In multiple regression models for the frequency of nighttime awakenings in infants, positive associations for infants falling asleep while feeding (vs. in bed alone) and side (vs. prone) sleep position were consistently observed after removing influential observations. Lower nighttime sleep efficiency (B =  - 0.08, 95%CI: - 0.13, - 0.02) and longer nighttime wake after sleep onset (B = 1.03, 95%CI: 0.41, 1.65) in mothers were associated with more frequent nighttime awakenings in infants. After removing influential observations, more frequent nighttime awakenings (B = 0.35; 95%CI: 0.09, 0.61) and longer total sleep duration (B = 0.33, 95%CI: 0.11, 0.55) in mothers were also associated with more frequent nighttime awakenings in infants. Sleep initiation methods with less parental involvement, and more continuous and efficient maternal nighttime sleep, tended to be associated with less interrupted infant sleep.

ABM Clinical Protocol #37: Physiological Infant Care-Managing Nighttime Breastfeeding in Young Infants

A central goal of the Academy of Breastfeeding Medicine (ABM) is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient. The ABM empowers health professionals to provide safe, inclusive, patient-centered, and evidence-based care. Pregnant and lactating people identify with a broad spectrum of genders, pronouns, and terms for feeding and parenting. There are two reasons ABM's use of gender-inclusive language may be transitional or inconsistent across protocols. First, gender-inclusive language is nuanced and evolving across languages, cultures, and countries. Second, foundational research has not adequately described the experiences of gender-diverse individuals. Therefore, ABM advocates for, and will strive to use language that is as inclusive and accurate as possible within this framework. For more explanation, please read ABM Position Statements on Infant Feeding and Lactation-Related Language and Gender (https://doi.org/10.1089/bfm.2021.29188.abm) and Breastfeeding As a Basic Human Right (https://doi.org/10.1089/bfm.2022.29216.abm).

Many faces of sleep regulation: beyond the time of day and prior wake time

The two-process model of sleep regulation posits two main processes regulating sleep: the circadian process controlled by the circadian clock and the homeostatic process that depends on the history of sleep and wakefulness. The model has provided a dominant conceptual framework for sleep research since its publication ~ 40 years ago. The time of day and prior wake time are the primary factors affecting the circadian and homeostatic processes, respectively. However, it is critical to consider other factors influencing sleep. Since sleep is incompatible with other behaviors, it is affected by the need for essential behaviors such as eating, foraging, mating, caring for offspring, and avoiding predators. Sleep is also affected by sensory inputs, sickness, increased need for memory consolidation after learning, and other factors. Here, we review multiple factors influencing sleep and discuss recent insights into the mechanisms balancing competing needs.

Changes in parental sleep from pregnancy to postpartum: A meta-analytic review of actigraphy studies

Sleep changes in new parents are widely observed but there is no extant meta-analysis of changes to sleep parameters in this group. We completed a meta-analysis of changes in actigraphy-measured parent sleep between pregnancy and the end of the first year of a child's life. A search of six databases was completed. Following review using predetermined inclusion and exclusion criteria, 16 papers were left for review. Data were extracted, analysed and each paper was reviewed for methodological quality. Where possible, subgroup analysis was completed based on time since birth and location of the study, and meta-regression of parent age. Parents' total sleep time and sleep efficiency were shown to decrease following the birth of a child, with wake after sleep onset increasing. This change was most notably observed in the first four weeks after birth. Up to 16 weeks post-birth, differences were still apparent, but sleep parameters were beginning to return to pre-birth levels. New parents experience a significant change in multiple sleep parameters following the birth of a child. Future data collection, using best practice actigraphy measurement, reporting a broader range of variables and including fathers, as well as mothers, is warranted.

Night Sleep and Parental Bedtime Practices in Low-Risk Preterm and Full-Term Late Talkers

Night sleep and parental bedtime practices have rarely been investigated in late talkers. This study aimed to explore: night sleep, parental bedtime practices, and their associations in late talkers as well as individual, socio-demographic, and socio-relational factors affecting them. Parents of 47 30-month-old late talkers, born low-risk preterm (n = 24) or full-term (n = 23), with an expressive vocabulary size ≤10th percentile measured by the MacArthur-Bates Communicative Development Inventory Words and Sentences, and normal cognitive abilities measured by the Bayley Scales, completed the Infant Sleep Questionnaire, the Parental Interactive Bedtime Behaviour Scale, and the Parenting Stress Index Short Form. Results showed slight settling difficulties, night wakings, and frequent co-sleeping in late talkers. Encouraging autonomy practices were frequently used by parents, rather than active physical comforting ones. Recurrent settling difficulties were reported by parents who often applied encouraging autonomy practices, whereas greater night waking problems and frequent co-sleeping were reported by parents who often left their child crying. Low-risk preterm birth and mother's parenting stress predicted total sleep difficulties and night wakings; first-born, high maternal education level and mother's parenting stress predicted settling difficulties; mother's parenting stress was the only predictor for co-sleeping and leaving to cry. These findings have relevant implications for improving late talkers' night sleep and their parents' bedtime practices.

Links between household and family social dynamics with sleep profiles among BaYaka foragers of the Congo Basin

Given the contributions of sleep to a range of health outcomes, there is substantial interest in ecological and environmental factors, including psychosocial contexts, that shape variation in sleep between individuals and populations. However, the links between social dynamics and sleep are not well-characterized beyond Euro-American settings, representing a gap in knowledge regarding the way that local socio-ecological conditions interrelate with sleep profiles across diverse settings. Here, we focused on data from a subsistence-level society in Republic of the Congo to test for links between the household/family social environment and sleep measures. Specifically, we used actigraphy-derived sleep data (N = 49; 318 nights) from two community locations (a village and rainforest camp) among BaYaka foragers, who are members of a remote, non-industrialized subsistence society in the Congo Basin. We drew on social dynamics that have been previously linked to sleep variation in Euro-American contexts, including: household crowding, same surface cosleeping, and marital conflict. We examined the following sleep measures: total sleep time (TST), total 24-h sleep time (TTST), and sleep quality (fragmentation). BaYaka adults had shorter and lower quality sleep when their shared sleeping space was more crowded. In the village, parents with breastfeeding-aged infants had longer TTST and higher quality sleep than adults without infants, contrasting with results from other cultural contexts. Based on peer rankings of marital conflict, husbands showed longer and higher quality sleep in less conflicted marriages. Women showed the opposite pattern. These counter-intuitive findings for women may reflect the limitations of the measurement for wives' marital experiences. In total, these results point to the importance of considering local socio-ecological conditions to sleep profiles and underscore the need for expanded study of sleep and health outcomes in settings where shared sleep in constrained space is routine practice.

Psychological Distress Prospectively Predicts Later Sleep Quality in a Sample of Black American Postpartum Mothers

Objective: Previous longitudinal studies have demonstrated prospective relationships between maternal sleep quality and subsequent psychological distress in the postpartum period. Despite evidence for prospective relationships between mood and subsequent sleep quality in adult populations, this direction has not been examined in postpartum women. We aimed to test prospective relationships between sleep quality and subsequent psychological distress, as well as the plausible reverse possibility, in a sample of Black American postpartum mothers (n = 146).Participants: Mothers were recruited prenatally from two hospitals in a Southeastern city of the United States. Eligible and interested mothers enrolled in a follow-up study on infant development. Data from the current study were obtained during the follow-up study.Method: Mothers reported on their psychological distress (i.e., anxiety, depression, stress) and sleep quality at 3- and 6-months postpartum. We performed hierarchical linear regressions to explore whether 1) maternal sleep quality at 3-months postpartum would predict maternal psychological distress at 6-months postpartum, after adjustment for mothers' earlier psychological distress, and 2) whether psychological distress at 3-months postpartum would predict maternal sleep quality at 6-months postpartum, after adjustment for mothers' earlier sleep quality.Results: Maternal sleep quality at 3-months postpartum was not a significant predictor of psychological distress at 6-months postpartum. However, maternal psychological distress at 3-months postpartum was a significant predictor of sleep quality at 6-months postpartum.Conclusions: Mothers' psychological distress earlier in the postpartum was a significant predictor of their later sleep quality. Replication is needed in large, prospective studies, with results stratified by race/ethnicity.

Evidence Base for 2022 Updated Recommendations for a Safe Infant Sleeping Environment to Reduce the Risk of Sleep-Related Infant Deaths

Every year in the United States, approximately 3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Statistical Classification of Diseases and Related Health Problems 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths have remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. In addition, additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, which is included in this issue.

A comparative study of mother-infant co-regulation of distance at home in Japan and Scotland

Mothers and infants co-regulate their distance from one another at home. Continuous, naturalistic home observations of the changes in mother-infant distance were carried out in Japan and Scotland during infant ages of 0-1, 6-7, and 12-13 months. This study examined mutual distance-increasing and distance-reducing behaviours, referred to as parent-infant 'centrifugalism' and 'centripetalism'. Cultural differences emerged in the modes of mother-infant distance co-regulation. Scottish mothers were more active in initiating contact and leaving infants alone to sleep, whereas Japanese mothers showed stronger infant-centredness by maintaining physical contact with infants when they fell asleep and reacting to their crying when they woke up. Age differences were found relating to decrease in sleep and increase in object play in the middle of the first year, which resulted in more separation within a 0.5 m distance at 6-7 months, a compromise between closeness and distancing between mothers and awake infants. Cultural and age differences in the co-regulation of mother-infant distance were discussed in relation to the development of locomotion, object play, and intention-reading.

The Effectiveness of Sleep Training: Fact or Fiction?

Introduction

In Western cultures, parents often view infant sleep as problematic. Family, friends, and doctors may advise parents to “sleep train” assuming it is safe and effective, without considering its possible side effects, including its impact on breastfeeding. Unfortunately, it may reduce night feeds and result in earlier supplementation or weaning. The larger question is whether sleep training is worth the risk (i.e., does it improve infant sleep?). Our goal was to examine the data on the effectiveness of sleep training interventions on infant/toddler sleep.

Methods

PubMed and Google Scholar were searched for specific terms to identify articles that included behavioral sleep interventions and objective measures of sleep pre-and postntervention. Two objective infant sleep measures were examined: Night wakings and total sleep duration. Articles were then reviewed for evidence of the effectiveness of these interventions to reduce night wakings and increase total sleep duration.

Results

Five articles were identified that met the criteria for inclusion. Overall, there was no evidence that sleep training improves infant sleep.

Applications for Practice

The claim that sleep training is effective in changing infant sleep is not warranted. Given the potential side effects on breastfeeding, parents should be cautioned about engaging these behavioral sleep interventions if they have breastfeeding goals they want to achieve.

Using complexity science to understand the role of co-sleeping (bedsharing) in mother-infant co-regulatory processes

Human infants spend most of their time sleeping, but over the first few years of life their sleep becomes regulated to coincide more closely with adult sleep (Galland et al., 2012; Paavonen et al., 2020). Evidence shows that co-sleeping played a role in the evolution of infant sleep regulation, as it is part of an ancient behavioral complex representing the biopsychosocial microenvironment in which human infants co-evolved with their mothers through millions of years of human history (Ball, 2003; McKenna 1986, 1990). This paper is a conceptual, interdisciplinary, integration of the literature on mother-infant co-sleeping and other mother-infant co-regulatory processes from an evolutionary (biological) perspective, using complexity science. Viewing the mother-infant dyad as a "complex adaptive system" (CAS) shows how the CAS fits assumptions of regulatory processes and reveals the role of the CAS in the ontogeny of mother-infant co-regulation of physiological (thermoregulation, breathing, circadian rhythm coordination, nighttime synchrony, and heart rate variability) and socioemotional (attachment and cortisol activity) development.

Directionality of the associations between bedsharing, maternal depressive symptoms, and infant sleep during the first 15 months of life

OBJECTIVES

To identify predictors of infant sleep arrangement and examine the directionality of the relationships between maternal depressive symptoms, infant sleep problems, and bedsharing.

DESIGN

Secondary analysis of longitudinal data from the Mothers and Others: Family-Based Obesity Prevention for Infants and Toddlers randomized trial.

SETTING

Central North Carolina, USA.

PARTICIPANTS

Four-hundred and twenty-eight predominantly low-income, non-Hispanic Black mother-infant pairs.

MEASUREMENTS

Data were collected at 28 weeks pregnancy and 1, 3, 6, 9, 12, and 15 months postpartum. Maternal depressive symptoms were measured using the Center for Epidemiological Studies Depression Scale and infant sleep variables were measured using the Brief Infant Sleep Questionnaire.

RESULTS

The prevalence of reported bedsharing increased from 16.7% at 1 month to 35.6% at 15 months postpartum. Bedsharing was associated with shortened breastfeeding duration and maternal perception of an infant sleep problem. Concurrently, maternal perception of an infant sleep problem, but not presence of maternal depressive symptoms, was associated with an increased likelihood of bedsharing. Longitudinally, neither maternal perception of an infant sleep problem nor presence of maternal depressive symptoms predicted bedsharing. Bedsharing predicted an increased likelihood of maternal perception of an infant sleep problem and presence of maternal depressive symptoms.

CONCLUSION

Prevalence of bedsharing increased over time and was predictive of maternal depressive symptoms. Providers should discuss the conflicting infant sleep recommendations with their patients and provide safe-sleep guidelines for mothers who intend to bedshare.

A Quantile Regression Analysis of Factors Associated with First-Time Maternal Fatigue in Korea

The aim of this cross-sectional study was to identify the factors associated with different percentiles of first-time maternal fatigue. A total of 123 first-time healthy mothers aged 18 years or older participated through an online survey. The fatigue was measured by the Korean version of the fatigue severity scale. Main variables were constructed based on the integrated fatigue model, which included mothers' sleep quality, parenting stress, the amount of free time mothers have, the number of the child's night wakings, general characteristics including socioeconomic status, and working status. Quantile regression was used to analyze the associated factors according to the fatigue level of first-time mothers with a young child. The mean age of the mothers and children were 32.11 years and 20.81 months, respectively. Mean fatigue score was 6.16 among the 75% quantile with high fatigue score. Lack of adequate free time in mothers, advanced maternal age, being a housewife, having a moderate income, and frequent night wakings of their child significantly increased fatigue among mothers in the third quantile of fatigue. To reduce fatigue, healthcare providers should focus on exploring ways to reduce maternal sleep disturbance and improve maternal sleep quality.

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.

Sleep-related parenting self-efficacy and parent-reported sleep in young children: A dyadic analysis of parental actor and partner effects

OBJECTIVES

The role of positive cognitions, particularly domain-specific sleep-related parenting self-efficacy (SPSE), for young children's sleep has received limited attention so far. The present study investigates possible interdependencies between maternal/paternal SPSE and parent-reported sleep problems in infants and toddlers.

DESIGN AND SETTING

Mother-father dyads participated in this cross-sectional German study and filled out questionnaires.

PARTICIPANTS

One hundred thirty-one parental dyads with children aged between 2 and 47 months (M = 19.4; standard deviation = 10.6) participated in the study.

MEASUREMENTS

Parents answered a questionnaire about their own SPSE and the Children's Sleep Habits Questionnaire-Infant Version about their child's sleep. Paired sample t tests and correlations were used to investigate parental differences and agreement. An actor-partner interdependence model to examine the relationship between maternal/paternal SPSE and parent-reported child sleep problems was estimated, controlling for child age and co-sleeping.

RESULTS

The results reveal no differences between parents regarding their own SPSE and between mother- and father-reported child sleep problems. Mothers and fathers showed significant agreement regarding their children's sleep problems. For both parents, significant actor effects between SPSE and child sleep emerged, with higher SPSE being related to fewer child sleep problems. For fathers, also partner effects were significant with higher paternal SPSE being related to fewer child sleep problems in the maternal report.

CONCLUSION

This study underlines the importance of considering mothers' and fathers' nonindependence in dyadic data analysis. Parenting self-efficacy might play a specific role in the context of young children's sleep and could be used for early intervention and prevention programs.

Early Childhood Co-Sleeping Predicts Behavior Problems in Preadolescence: A Prospective Cohort Study

OBJECTIVE/BACKGROUND

Co-sleeping is common practice around the globe. The relationship between early childhood co-sleeping and adolescent behavior problems remains uncertain. We aim to identify whether early childhood co-sleeping can predict behavior problems in preadolescence.

PARTICIPANTS

A cohort of 1,656 Chinese preschool children were followed up in adolescence.

METHODS

Prospective cohort study design involving two waves of data collection from the China Jintan Cohort (1,656 children aged 3-5 years). Co-sleeping history was collected at 3-5-years-old via parent-reported questionnaire at wave I data collection. Behavior problems were measured twice in childhood and preadolescence, respectively. Adolescent behavior problems were measured by integrating data from self-report, parent-report and teacher-report using the Achenbach System of Empirically Based Assessment. Predictions were assessed using the general linear model with mixed effects on the inverse probability weight propensity-matched sample.

RESULTS

1,656 children comprising 55.6% boys aged 4.9 ± 0.6 were initially enrolled in the first wave of data collection. In the second wave of data collection, 1,274 children were 10.99 ± 0.74 (76.9%) aged 10-13 years were retained. Early childhood co-sleeping is significantly associated with increased behavior problems in childhood (Odds Ratio [OR] 1.22-2.06, ps<0.03) and preadolescence (OR 1.40-2.27, ps<0.02). Moreover, co-sleeping history significantly predicted multiscale increase in internal (OR 1.63-2.61, ps<0.02) and external behavior problems in adolescence.

CONCLUSIONS

Early childhood co-sleeping is associated with multiple behavioral problems reported by parents, teachers, and children themselves. Early childhood co-sleeping predicts preadolescent internalizing and externalizing behavior after controlling for baseline behavior problems.

Parents' strategies and advice for creating a positive sleep situation in the family

AIM

The aim of this study was to describe the experience-based knowledge of parents of children aged 0-3 years for creating a positive sleep situation in the family.

DESIGN

This study has a qualitative design. Data were collected using an online survey and analysed using the critical incident technique.

METHODS

The study participants were recruited through an announcement posted in parenting groups on a social media platform in September 2018. A total of 93 parents answered the questionnaire; 76 of the parents matched the study's selection criteria, and their responses were included in the analysis.

RESULTS

The results are presented from the two main questions in the survey: "Strategies for creating a positive sleep situation" and "Advice to new parents regarding sleep". Having routines and reading the child's signals were important strategies, as were creating good conditions for sleep and making sure the child was well-fed and content at bedtime. Winding down and giving the child closeness and touch was described as important, and some parents would co-sleep to soothe the child quickly and create a sense of security and belonging. Parents' most frequent advice to other parents was to accept the situation and to let go of the idea that the child should sleep without waking up in a separate bed or room.

CONCLUSION

Personal preferences and needs are likely to vary among individuals, and it is important that nurses tailor sleep advice in accordance with families' preferences and needs, taking individual variations and views into account.

A meta-analysis of accelerometer sleep outcomes in healthy children based on the Sadeh algorithm: the influence of child and device characteristics

STUDY OBJECTIVES

Children often experience sleep problems, with a negative impact on mood, behavior, cognitive function, and other aspects of mental and physical health. Accelerometers are widely used to assess sleep, but general reference values for healthy children do not yet exist. The aim of this meta-analysis was to determine mean values for wake after sleep onset (WASO), sleep efficiency (SE), total sleep time (TST) and sleep onset latency (SOL), and to determine the effect of child and accelerometer-characteristics.

METHODS

A search included studies with healthy children, 0-18 years, reporting WASO, SE, TST, and/or SOL, calculated with the Sadeh algorithm. Meta-analyses with random effects produced pooled estimate means per outcome. Meta-regression analyses determined the effect of age, sex, placement site and accelerometer type.

RESULTS

Eighty-three studies (9,068 participants) were included. Pooled means were 63 min (95% CI 57 to 69) for WASO, 88% (95% CI 87 to 89) for SE, 477 min (95% CI 464 to 491) for TST and 19 min (95% CI 17 to 22) for SOL. Heterogeneity was high (95%-99%). TST decreased with age and there was an age-effect on SOL. SE differed between wrist and ankle (used in age 0-24 months) placement, and between piezoelectric and MEMS-type accelerometers. No differences were found between boys and girls, although this number of studies was small.

CONCLUSIONS

We found differences in almost all investigated outcomes and heterogeneity was high. Therefore, we advise to use a study-specific control sample until more robust reference values are available. Future research should narrow the methodological heterogeneity and produce larger datasets, needed to establish these reference values.

Determinants of postpartum sleep duration and sleep efficiency in minority women

STUDY OBJECTIVES

To examine demographic, psychosocial, and behavioral determinants of postpartum sleep duration and sleep efficiency among a cohort of black and Latina women.

METHODS

Data were from 148 women (67% black, 32% Latina) at 5 months postpartum, recruited from an academic medical center in Philadelphia. Relevant demographic, psychosocial and behavioral predictors were assessed via questionnaire. Nocturnal sleep was objectively measured for 1 week using wrist actigraphy. Sleep duration was examined as a continuous variable and in categories (<7 versus ≥7 h per night); sleep efficiency was examined as a continuous variable. Independent multiple linear regression models were built to evaluate significant determinants of sleep.

RESULTS

Adjusted models revealed that breastfeeding, having a bedtime after midnight, and being employed were associated with shorter sleep duration (-25-33 min, all p < 0.05). Multiparity, being unmarried, being employed, breastfeeding, having a bedtime after midnight, bedsharing, and responding to infant awakenings by getting up immediately rather than waiting a few minutes to see if the infant fell back asleep, were all significant determinants of sleeping <7 h per night (OR varying: 2.29-4.59, all p < 0.05). Bedsharing was the only variable identified from the multiple regression model that associated with poorer sleep efficiency (-3.8%, p < 0.05).

CONCLUSIONS

Findings may inform interventions for improving postpartum sleep in socioeconomically disadvantaged, racial/ethnic minority postpartum women.

Emergence of racial/ethnic and socioeconomic differences in objectively measured sleep-wake patterns in early infancy: results of the Rise & SHINE study

STUDY OBJECTIVES

To characterize objectively assessed sleep-wake patterns in infants at approximately 1 month and 6 months and examine the differences among infants with different racial/ethnic backgrounds and household socioeconomic status (SES).

METHODS

Full-term healthy singletons wore an ankle-placed actigraph at approximately 1 month and 6 months and parents completed sleep diaries. Associations of racial/ethnic and socioeconomic indices with sleep outcomes were examined using multivariable analyses. Covariates included sex, birth weight for gestational age z-score, age at assessment, maternal education, household income, bed-sharing, and breastfeeding.

RESULTS

The sample included 306 infants, of whom 51% were female, 42.5% non-Hispanic white, 32.7% Hispanic, 17.3% Asian, and 7.5% black. Between 1 month and 6 months, night sleep duration increased by 65.7 minutes (95% CI: 55.4, 76.0), night awakenings decreased by 2.2 episodes (2.0, 2.4), and daytime sleep duration decreased by 73.3 minutes (66.4, 80.2). Compared to change in night sleep duration over this development period for white infants (82.3 minutes [66.5, 98.0]), night sleep increased less for Hispanic (48.9 minutes [30.8, 66.9]) and black infants (31.6 minutes [-5.9, 69.1]). Night sleep duration also increased less for infants with lower maternal education and household income. Asian infants had more frequent night awakenings. Adjustment for maternal education and household income attenuated all observed day and night sleep duration differences other than in Asians, where persistently reduced nighttime sleep at 6 months was observed.

CONCLUSIONS

Racial/ethnic differences in sleep emerge in early infancy. Night and 24-hour sleep durations increase less in Hispanic and black infants compared to white infants, with differences largely explained by SES.

Daytime nap and nighttime breastfeeding are associated with toddlers' nighttime sleep

The purpose of the present study is to examine the association between toddlers' sleep arrangements and their nighttime sleep duration and other sleep variables. For this investigation, we performed a study in which child activity and sleep levels were recorded using actigraphy. The parents of 1.5-year-old toddlers (n = 106) were asked to attach an actigraphy unit to their child’s waist with an adjustable elastic belt and complete a sleep diary for 7 consecutive days. Questionnaires were used to assess the sleep arrangements of the toddlers. There was a significant negative correlation between nap duration and nighttime sleep duration, suggesting that longer nap sleep induces shorter nighttime sleep duration. Among the sleep arrangements, such as nighttime breastfeeding or co-sleeping, only nighttime breastfeeding predicted shorter nighttime sleep duration. Our findings indicate that shorter naps induce a longer nighttime sleep in 1.5-year-old toddlers while nighttime breastfeeding decreases their nighttime sleep duration.

The effects of bed sharing on sleep: From partners to pets

BACKGROUND

Bed sharing is common practice across the global population. However, the vast majority of research on bed sharing has focused solely on mother-infant bed sharing.

METHODS

Here, we provide a holistic review of research on bed sharing. Articles investigating the relationship between bed sharing and sleep were identified in 4 dyad categories: (1) parent and child, (2) couples, (3) siblings, and (4) pet owners and pets. Of interest was whether sleep-promoting factors such as psychological comfort were generalizable across bed-sharing dyads; alternatively, sleep-demoting factors such as movement or heat may be commonalities.

RESULTS

We found that, across dyad types, in general, subjective reports of sleep quality were better when bed sharing despite generally worse objective measures of sleep.

CONCLUSIONS

Understanding bed sharing is important to treating sleep disturbances, given the prevalence of shared beds. This scoping review points to critical gaps in our understanding of bed sharing that motivate future research.

Mothers' and fathers' sleep: Is there a difference between first-time and experienced parents of 6-month-olds?

Sleep disruption and deprivation are highly prevalent among parents of an infant. However, most postpartum sleep studies focus solely on mothers, and few studies have investigated whether sleep differs between first-time and experienced parents. The present study aimed to determine whether self-reported sleep duration and quality differ between first-time and experienced mothers and fathers during the postpartum period. A total of 111 parents (54 couples and three single mothers) of 6-month-old infants completed a 2-week sleep diary to evaluate measures of sleep duration, sleep continuity, and sleep quality. An analysis of covariance model was used to compare the sleep variables of first-time to experienced parents. Breastfeeding frequency, infant sleep location, depression, education, and work status were used as co-variables. First-time mothers reported a longer consecutive nocturnal sleep duration (mean [SEM] 297.34 [17.15] versus 246.01 [14.79] min, p < .05), fewer nocturnal awakenings (mean [SEM] 1.57 [0.20] versus 2.12 [0.17], p < .05), and rated their sleep quality higher (mean [SEM] score 7.07 [0.36] versus 5.97 [0.30], p < .05) than experienced mothers, while total nocturnal sleep duration did not differ. There were no differences in subjective sleep measures between first-time and experienced fathers. The present study indicates that experienced mothers reported more fragmented sleep and perceived having worse sleep quality than first-time mothers, but that paternal sleep did not differ as a function of parental experience. These findings have clinical implications for healthcare professionals working with families of various configurations and sizes.

Actigraphy in sleep research with infants and young children: Current practices and future benefits of standardized reporting

Actigraphy is a cost‐efficient method to estimate sleep–wake patterns over long periods in natural settings. However, the lack of methodological standards in actigraphy research complicates the generalization of outcomes. A rapidly growing methodological diversity is visible in the field, which increasingly necessitates the detailed reporting of methodology. We address this problem and evaluate the current state of the art and recent methodological developments in actigraphy reporting with a special focus on infants and young children. Through a systematic literature search on PubMed (keywords: sleep, actigraphy, child *, preschool, children, infant), we identified 126 recent articles (published since 2012), which were classified and evaluated for reporting of actigraphy. Results show that all studies report on the number of days/nights the actigraph was worn. Reporting was good with respect to device model, placement and sleep diary, whereas reporting was worse for epoch length, algorithm, artefact identification, data loss and definition of variables. In the studies with infants only (n = 58), the majority of articles (62.1%) reported a recording of actigraphy that was continuous across 24 hr. Of these, 23 articles (63.9%) analysed the continuous 24‐hr data and merely a fifth used actigraphy to quantify daytime sleep. In comparison with an evaluation in 2012, we observed small improvements in reporting of actigraphy methodology. We propose stricter adherence to standards in reporting methodology in order to streamline actigraphy research with infants and young children, to improve comparability and to facilitate big data ventures in the sleep community.

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.

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.

Temporal Patterns of Infant Regulatory Behaviors in Relation to Maternal Mood and Soothing Strategies

This study investigates the temporal patterning of infant self-regulatory behaviors (crying/fussing, sleeping) in relation to both infant (age, sex, regulatory problems) and maternal variables (soothing behaviors, mood). Self-regulatory and soothing behaviors were assessed in 121 mother-infant dyads (4-44 weeks) by the Baby's Day Diary at 5 min intervals over 3 days. Further infant characteristics and maternal mood were assessed by questionnaires (DASS, CES-D, STAI) and the Diagnostic Interview for the Assessment of Regulatory Problems in Infancy and Toddlerhood. Data were analyzed using generalized additive mixed models. Negative maternal mood was associated with a deviant course of crying/fussing during the day. Body contact was associated with reduced variability in the 24 h course of sleep. Mother-infant transactional processes-above and beyond known relationships with overall levels of crying/fussing and sleeping-might play out on the temporal dimension of infant regulatory behaviors.

Sleep in parents of preterm infants: A systematic review

BACKGROUND

Sleep disruption during the first postpartum year is associated with several negative health outcomes including postpartum depression. Such disruption may be a greater issue for parents of preterm neonates, yet literature on this subject has not been critically reviewed.

OBJECTIVE

To synthesize literature on sleep quantity, sleep quality, and factors influencing sleep among parents of preterm infants during infant hospitalization and following discharge.

DESIGN

A systematic review.

DATA SOURCES

Medline, EMBASE, CINAHL, PsycINFO, Scopus, and Cochrane Database of Systematic Reviews were searched from their inception to February 2017.

METHODS

Potentially eligible citations were reviewed by two independent reviewers. Both quantitative and qualitative studies were eligible for inclusion. Data on eligible studies and review outcomes were extracted using a customized form.

FINDINGS

Eighteen reports from 16 studies met inclusion criteria. Four studies included a control group of parents of full-term infants. Three studies reported sleep quantity means, of which only one provided values for an exclusive sample of mothers of preterm infants and found on average, mothers obtained 6.3 h of sleep/day in the first 5-10 days. Twelve studies reported on sleep quality; most (n = 10) relied on self-reported measures and identified poor subjective sleep quality whereas two studies objectively measured sleep of poor quality. Parental stress was the most consistent factor associated with sleep quality.

CONCLUSION AND IMPLICATIONS

Quality and quantity of sleep among parents of preterm infants is inadequate and may negatively influence family health outcomes. Further research on correlates and changes in sleep is required to identify at-risk parents and inform targeted clinical recommendations and interventions aimed at maximizing sleep for parents of preterm infants.

The Association of Daytime Maternal Napping and Exercise With Nighttime Sleep in First-Time Mothers Between 3 and 6 Months Postpartum

OBJECTIVE

This study investigated the relationship of daytime maternal napping, exercise, caffeine, and alcohol intake to objective and subjective sleep indices.

PARTICIPANTS

Sixty healthy, nondepressed, first-time mothers between 3 and 6 months postpartum.

METHODS

Seven consecutive days of online behavior diaries, sleep diaries, and wrist actigraphy, collecting Total Sleep Time (TST), Sleep Onset Latency (SOL), and Wake After Sleep Onset (WASO).

RESULTS

After controlling for infant age, employment status, infant feeding method, and infant sleeping location, mixed linear models showed that longer average exercise durations were associated with longer average TST, and longer average nap durations were associated with longer average WASO durations. Significant within-person differences in TST and SOL were also observed, such that, on days when participants exercised and napped longer than average, their respective TST and SOL durations that night were longer.

CONCLUSION

Shorter nap durations and longer exercise durations were associated with longer TST, shorter SOL, and reduced WASO. Even small changes in daily exercise and napping behaviors could lead to reliable improvements in postpartum maternal sleep.

Parent-Infant Room Sharing During the First Months of Life: Longitudinal Links With Behavior During Middle Childhood

Current recommendations encourage parent–infant room sharing for the first 6 months of life. This longitudinal study (N = 193) is the first to examine long‐term relations of early room sharing with three domains of child behavior: sleep, behavior problems, and prosocial behavior. Information on room sharing was collected daily for infants’ first 6 months. At ages 6, 7, and 8 years, outcomes were assessed with maternal and teacher questionnaires and behavioral observations. Early room sharing was not related to sleep problems or behavior problems. Additionally, more weeks of room sharing were positively related to higher maternal ratings of child sleep quality and more prosocial behavior. In conclusion, early room sharing appears to be related to positive, but not negative, behavior outcomes in middle childhood.