What are postpartum women doing while the rest of the world is asleep?

Large individual differences characterize maternal postpartum sleep and adjustment. Our goal was to explore aspects of mothers' nocturnal environments and behaviours that may explain differences in postpartum adjustment. A total of 201 mothers of infants aged 0-6 months completed an online survey with demographics, number and duration of nocturnal awakenings, caretaking behaviours, environment and nocturnal activities during 'one typical night during the past week'. Mothers reported 2.9 [standard deviation (SD) ± 1.7] nocturnal awakenings, each lasting 33.9 (SD ± 22.5) min. Infant age was related inversely to duration but unrelated to number of awakenings. Falling asleep while feeding was less frequent among exclusively formula-feeders. Among the entire sample, mothers used a cellphone (59%), backlit tablet (25%), TV (20%) and computer (16%) during nocturnal awakenings. Watching TV and using a computer were each associated with longer nocturnal awakenings. Eighty-nine per cent of women used ≥1 extra light source during nocturnal awakenings: night light (35%), light from a cracked door (28%), desk lamp (25%), electronic device (19%) or room light (14%). Light source(s) was unrelated to number or duration of nocturnal awakenings. These data suggest that, although supplemental light sources were not associated with awakenings, TV and computer use accounted for longer awakenings. Feeding method and technology use may help to explain individual differences in postpartum adjustments and may be targets for more effective interventions.

Sleep and sleepiness among first-time postpartum parents: a field- and laboratory-based multimethod assessment.

The study aim was to compare sleep, sleepiness, fatigue, and neurobehavioral performance among first-time mothers and fathers during their early postpartum period. Participants were 21 first-time postpartum mother-father dyads (N = 42) and seven childless control dyads (N = 14). Within their natural environment, participants completed 1 week of wrist actigraphy monitoring, along with multi-day self-administered sleepiness, fatigue, and neurobehavioral performance measures. The assessment week was followed by an objective laboratory-based test of sleepiness. Mothers obtained more sleep compared to fathers, but mothers' sleep was more disturbed by awakenings. Fathers had greater objectively measured sleepiness than mothers. Mothers and fathers did not differ on subjectively measured sleep quality, sleepiness, or fatigue; however, mothers had worse neurobehavioral performance than fathers. Compared to control dyads, postpartum parents experienced greater sleep disturbance, sleepiness, and sleepiness-associated impairments. Study results can inform social policy, postpartum sleep intervention development, and research on postpartum family systems and mechanisms that propagate sleepiness.

Movement toward a novel activity monitoring device.

PURPOSE: Although polysomnography is necessary for diagnosis of most sleep disorders, it is also expensive, time-consuming, intrusive, and interferes with sleep. Field-based activity monitoring is increasingly used as an alternative measure that can be used to answer certain clinical and research questions. The purpose of this study was to evaluate the reliability and validity of a novel activity monitoring device (Fitbit) compared to both polysomnography and standard actigraphy (Actiwatch-64). METHODS: To test validity, simultaneous Fitbit and actigraph were worn during standard overnight polysomnography by 24 healthy adults at the West Virginia University sleep research laboratory. To test inter-Fitbit reliability, three participants also wore two of the Fitbit devices overnight at home. RESULTS: Fitbit showed high intradevice reliability = 96.5-99.1. Fitbit and actigraph differed significantly on recorded total sleep time and sleep efficiency between each other and polysomnography. Bland-Altman plots indicated that both Fitbit and actigraph overestimated sleep efficiency and total sleep time. Sensitivity of both Fitbit and actigraphy for accurately identifying sleep was high within all sleep stages and during arousals; specificity of both Fitbit and actigraph for accurately identifying wake was poor. Specificity of actigraph was higher except for wake before sleep onset; sensitivity of Fitbit was higher in all sleep stages and during arousals. CONCLUSIONS: The web-based Fitbit, available at a markedly reduced price and with several convenience factors compared to standard actigraphy, may be an acceptable activity measurement instrument for use with normative populations. However, Fitbit has the same specificity limitations as actigraphy; both devices consistently misidentify wake as sleep and thus overestimate both sleep time and quality. Use of the Fitbit will also require specific validation before it can be used to assess disordered populations and or different age groups.

Perception of partner sleep and mood: postpartum couples' relationship satisfaction.

Separate research areas indicate that sleep quality, mood, and relationship satisfaction decline among couples during the postpartum period. Furthermore, accurate partner perceptions are associated with positive relationship qualities. In this study, 21 first-time postpartum mother-father dyads, contributed 1 week of continuous wrist actigraphy along with concurrent subjective Palm Pilot monitoring to provide objective and subjective sleep measures. Parents also reported on their own as well as their perception of their partners' sleep, mood, and relationship satisfaction. Greater objectively measured total sleep time was associated with greater relationship satisfaction. Mothers (a) underestimated fathers' self-reported frequency of nocturnal awakenings, as well as (b) relationship satisfaction, and (c) overestimated fathers' self-reported sleep quality. Fathers (a) underestimated mothers' self-reported duration of wake at night, as well as (b) sleep quality, and (c) overestimated mothers' self-reported mood disturbance. Preventative measures that target sleep and improvement in perception of partner's experiences could be used to buffer against decreases in relationship satisfaction among new parents.

Risk for sleep-disordered breathing and home and classroom behavior in Hispanic preschoolers.

Pediatric sleep-disordered breathing (SDB) is known to negatively impact home and classroom behavior. Preschool-age Hispanic children from Spanish-speaking households are at elevated risk for poor school readiness. The authors used a multi-informant approach to assess home and preschool behavior among Hispanic children at risk for SDB (n = 67). Higher parent-reported SDB risk and elevated snoring were associated with parent- and teacher-reported problem behaviors and poorer teacher-reported classroom executive function among boys; elevated snoring was associated with internalizing behaviors among girls. Elevated snoring may be associated with problems related to impaired inhibitory self-control, suggesting the need for early intervention in order to improve school readiness among these a priori defined at-risk Hispanic children.

Assessing the efficacy to conduct the multiple sleep latency test with actigraphy.

This study explored the efficacy of 1 actigraphy (ACT) brand, at different analytic settings, for use to administer the Multiple Sleep Latency Test (MSLT). Forty-one first-time postpartum mother and father participants were administered the MSLT with concurrent ACT. To identify ACT sleep onset latency (SOL), ACT signals were interpreted with iterations of different "wake threshold value" (WTV) and "immobile minutes for sleep onset" value (IMV) settings. The different iterations of ACT-SOL values were compared to MSLT-SOL values. The WTV settings did not affect ACT-SOL, but the ACT-SOL and MSLT-SOL significantly differed at each ACT-IMV setting. ACT consistently identified SOL too soon; however, future research, along with technological innovation, may identify a viable methodology to conduct an ambulatory MSLT.

Normative longitudinal maternal sleep: the first 4 postpartum months.

OBJECTIVE: To describe the normative course of maternal sleep during the first 4 months postpartum. STUDY DESIGN: Sleep was objectively measured using continuous wrist actigraphy. This was a longitudinal, field-based assessment of nocturnal sleep during postpartum weeks 2 through 16. Fifty mothers participated during postpartum weeks 2 through 13; 24 participated during postpartum weeks 9 through 16. RESULTS: Maternal nocturnal sleep time was 7.2 (SD ± 0.95) hours and did not change significantly across postpartum weeks 2 through 16. Maternal sleep efficiency did improve across weeks 2 (79.7%; SD ± 5.5) through 16 (90.2%; SD ± 3.5) as a function of decreased sleep fragmentation across weeks 2 (21.7; SD ± 5.2) through 16 (12.8; SD ± 3.3). CONCLUSION: Though postpartum mothers' total sleep time was higher than expected during the initial postpartum months, this sleep was highly fragmented (similar to fragmenting sleep disorders) and inefficient. This profile of disturbed sleep should be considered in intervention designs and family leave policies.

Effects of two types of ambient sound during sleep.

This field study investigated whether either of two ambient sounds would improve objective sleep (via actigraphy), subjective sleep report, or morning psychomotor performance among 28 adults with self-described disturbed sleep. Nights 1 and 4 were soundless baseline and washout, respectively. On Nights 2 and 3 and 5 and 6, participants listened to double-blind counterbalanced paired nights of novel Sound A and a commercially available Sound B. Compared to baseline and washout, participants reported fewer awakenings during both Sound A and Sound B; actigraphically measured sleep was affected by Sound B but not Sound A. "Improvements" in sleep during the second exposure night probably reflect an increase in homeostatic sleep drive from sleep disturbance on the first exposure night. Differences between sounds were accounted for by user volume settings. Neither sound led to differences in psychomotor performance.

Sleep: A Pathway Linking Personality to Mortality Risk.

Personality and sleep predict longevity; however, no investigation has tested whether sleep mediates this association. Thus, we tested this effect across a 20-year follow-up (N = 3,759) in the Midlife Development in the United States cohort (baseline M age = 47.15) using proportional hazards in a structural equation modeling framework. Lower conscientiousness predicted increased death risk via the direct, indirect, and total effect of quadratic sleep duration. Although there were no other direct personality-mortality effects, higher neuroticism and agreeableness and lower conscientiousness predicted increased death risk via the joint indirect effects of quadratic sleep duration and higher daytime dysfunction. Lower extraversion predicted increased mortality risk via the indirect effect of daytime dysfunction. Our findings have implications for personality-based health interventions.

Long-term effects of pregnancy and childbirth on sleep satisfaction and duration of first-time and experienced mothers and fathers.

STUDY OBJECTIVES: To examine the changes in mothers' and fathers' sleep satisfaction and sleep duration across prepregnancy, pregnancy, and the postpartum period of up to 6 years after birth; it also sought to determine potential protective and risk factors for sleep during that time. METHODS: Participants in a large population-representative panel study from Germany reported sleep satisfaction and sleep duration in yearly interviews. During the observation period (2008-2015), 2541 women and 2118 men reported the birth of their first, second, or third child and provided longitudinal data for analysis. Fixed-effects regression models were used to analyze changes in sleep associated with childbirth. RESULTS: Sleep satisfaction and duration sharply declined with childbirth and reached a nadir during the first 3 months postpartum, with women more strongly affected (sleep satisfaction reduction compared with prepregnancy: women, 1.81 points on a 0 to 10 scale, d = 0.79 vs. men, 0.37 points, d = 0.16; sleep duration reduction compared with prepregnancy: women, 62 min, d = 0.90 vs. men, 13 min, d = 0.19). In both women and men, sleep satisfaction and duration did not fully recover for up to 6 years after the birth of their first child. Breastfeeding was associated with a slight decrease in maternal sleep satisfaction (0.72 points, d = 0.32) and duration (14 min, d = 0.21). Parental age, household income, and dual vs. single parenting were unrelated, or only very weakly related, to improved sleep. CONCLUSIONS: Following the sharp decline in sleep satisfaction and duration in the first months postpartum, neither mothers' nor fathers' sleep fully recovers to prepregnancy levels up to 6 years after the birth of their first child.

Breastfeeding Duration Is Associated with Regional, but Not Global, Differences in White Matter Tracts.

Extended breastfeeding through infancy confers benefits on neurocognitive performance and intelligence tests, though few have examined the biological basis of these effects. To investigate correlations with breastfeeding, we examined the major white matter tracts in 4-8 year-old children using diffusion tensor imaging and volumetric measurements of the corpus callosum. We found a significant correlation between the duration of infant breastfeeding and fractional anisotropy scores in left-lateralized white matter tracts, including the left superior longitudinal fasciculus and left angular bundle, which is indicative of greater intrahemispheric connectivity. However, in contrast to expectations from earlier studies, no correlations were observed with corpus callosum size, and thus no correlations were observed when using such measures of global interhemispheric white matter connectivity development. These findings suggest a complex but significant positive association between breastfeeding duration and white matter connectivity, including in pathways known to be functionally relevant for reading and language development.

Sleep Validity of a Non-Contact Bedside Movement and Respiration-Sensing Device.

STUDY OBJECTIVES: To assess the sleep detection and staging validity of a non-contact, commercially available bedside bio-motion sensing device (S+, ResMed) and evaluate the impact of algorithm updates. METHODS: Polysomnography data from 27 healthy adult participants was compared epoch-by-epoch to synchronized data that were recorded and staged by actigraphy and S+. An update to the S+ algorithm (common in the rapidly evolving commercial sleep tracker industry) permitted comparison of the original (S+V1) and updated (S+V2) versions. RESULTS: Sleep detection accuracy by S+V1 (93.3%), S+V2 (93.8%), and actigraphy (96.0%) was high; wake detection accuracy by each (69.6%, 73.1%, and 47.9%, respectively) was low. Higher overall S+ specificity, compared to actigraphy, was driven by higher accuracy in detecting wake before sleep onset (WBSO), which differed between S+V2 (90.4%) and actigraphy (46.5%). Stage detection accuracy by the S+ did not exceed 67.6% (for stage N2 sleep, by S+V2) for any stage. Performance is compared to previously established variance in polysomnography scored by humans: a performance standard which commercial devices should ideally strive to reach. CONCLUSIONS: Similar limitations in detecting wake after sleep onset (WASO) were found for the S+ as have been previously reported for actigraphy and other commercial sleep tracking devices. S+ WBSO detection was higher than actigraphy, and S+V2 algorithm further improved WASO accuracy. Researchers and clinicians should remain aware of the potential for algorithm updates to impact validity. COMMENTARY: A commentary on this article appears in this issue on page 935.

Beyond the Bayley: Neurocognitive Assessments of Development During Infancy and Toddlerhood.

The use of global, standardized instruments is conventional among clinicians and researchers interested in assessing neurocognitive development. Exclusively relying on these tests for evaluating effects may underestimate or miss specific effects on early cognition. The goal of this review is to identify alternative measures for possible inclusion in future clinical trials and interventions evaluating early neurocognitive development. The domains included for consideration are attention, memory, executive function, language, and socioemotional development. Although domain-based tests are limited, as psychometric properties have not yet been well-established, this review includes tasks and paradigms that have been reliably used across various developmental psychology laboratories.

Risk for sleep-disordered breathing and executive function in preschoolers.

BACKGROUND: Pediatric sleep-disordered breathing is known to negatively impact cognitive development. While a theoretical basis has been proposed for the developmental effect of pediatric sleep-disordered breathing on executive function specifically, this had not been directly examined among preschool-age children. This population may be particularly vulnerable if school-readiness is compromised. The purpose of the current study was to use a multi-dimensional approach to assessing executive function among preschool-age children at risk for sleep-disordered breathing. METHODS: Thirty-nine preschool children were administered executive function tasks assessing the dimensions of inhibition, working memory, and planning as part of a larger study. A parent or guardian completed a validated questionnaire concerning the child's snoring and other behaviors indicating risk for sleep-disordered breathing. RESULTS: After controlling for age in a series of regressions, higher parent-reported risk for sleep-disordered breathing was associated with substantially lower performance on each executive function dimension. In comparing the group means of children at high and low risk for sleep-disordered breathing, the single snoring frequency item also showed that children who snored frequently or almost always had lower performance on each executive function dimension. CONCLUSIONS: The results suggest that sleep-disordered breathing may be associated with impaired executive function in preschoolers, with its strongest impact on the inhibition dimension, further emphasizing the importance of early intervention for sleep-disordered breathing in this early age group.

Nocturnal body position in sleeping children with and without obstructive sleep apnea.

OBJECTIVES: To assess whether body position during sleep differs among children with obstructive sleep apnea (OSAS) and controls, and to assess the effects of body position, obesity, and tonsillar size on respiratory disturbance. Four hundred and thirty consecutive children with polysomnographically demonstrated OSAS. And 185 age-, gender-, and ethnically matched children (Controls) were compared. The effect of sleep body position on respiratory disturbance was examined in OSAS, and also in relation to obesity and tonsillar size. Children with OSAS spent more time in the supine position than Controls (P<0.01), with less time spent in the side position (P<0.005). Obstructive apnea and hypopnea index (AHI) was similar in the three sleep-related positions, but apnea index (AI) was significantly greater (4.6 +/- 0.7/hr TST) in the supine position than in the side position (2.7 +/- 0.3/hr TST; P<0.001) or prone position (3.3 +/- 0.5/hr TST; P<0.01). Tonsillar size was not a contributing factor to positional differences in AI or AHI. Obese OSAS children had increased prone position (20.4 +/- 2.0%TST vs. non-obese: 10.9 +/- 2.5%TST; P<0.05), and displayed increased AHI and AI while supine. Non-obese OSAS increased AHI in prone or side positions compared to supine (P<0.01), with no significant differences in position-dependent AI. Children with OSAS spend more time sleeping supine and less time on the side. Obese children with OSAS are more likely to sleep prone, suggesting that this position may promote upper airway patency in the presence of obesity. Although tonsillar size is not associated with positional differences in breathing, the presence or absence of obesity markedly modifies the effect of body position on respiratory disturbance.

Digital Media and Sleep in Childhood and Adolescence.

Given the pervasive use of screen-based media and the high prevalence of insufficient sleep among American youth and teenagers, this brief report summarizes the literature on electronic media and sleep and provides research recommendations. Recent systematic reviews of the literature reveal that the vast majority of studies find an adverse association between screen-based media consumption and sleep health, primarily via delayed bedtimes and reduced total sleep duration. The underlying mechanisms of these associations likely include the following: (1) time displacement (ie, time spent on screens replaces time spent sleeping and other activities); (2) psychological stimulation based on media content; and (3) the effects of light emitted from devices on circadian timing, sleep physiology, and alertness. Much of our current understanding of these processes, however, is limited by cross-sectional, observational, and self-reported data. Further experimental and observational research is needed to elucidate how the digital revolution is altering sleep and circadian rhythms across development (infancy to adulthood) as pathways to poor health, learning, and safety outcomes (eg, obesity, depression, risk-taking).

Toddler behavior following polysomnography: effects of unintended sleep disturbance.

STUDY OBJECTIVES: Childhood sleep disorders are consistently shown to affect behavior and cognition, but first-night effects on these measures are generally unknown. We sought to examine how sleep in the home versus the laboratory differed among healthy toddlers and how such differences relate to standardized scores on assessments the morning following polysomnography. DESIGN, SETTING, AND PARTICIPANTS: Twenty healthy 14-month-olds wore actigraphs during nighttime sleep at home for 5 nights preceding and during standard overnight laboratory polysomnography. The Bayley Scales of Infant Development (BSID-II) were administered once the morning after polysomnography. MEASUREMENTS AND RESULTS: All subjects had normal polysomnography. Sleep-start times at home and during polysomnography did not differ, whereas, during polysomnography, subjects awoke earlier (p = .008, d = .58), their total sleep time (p <. 001, d = 1.1) and sleep efficiency (p = .004, d = .57) were reduced, and they had shorter sleep-bout lengths (p = .004, d = .03), less immobility (p = .003, d = .62), and greater average activity during sleep (p <. 001, d = .98). Standardized assessments were not affected by differences between home and polysomnography night sleep, but children with greater emotional regulation difficulty had a lower percentage of immobility (r = -0.67, p = .001) and increased sleep fragmentation (r = -0.60, p = .005) during polysomnography. CONCLUSIONS: Although sleep-onset times were preserved, sleep in the laboratory was disrupted, compared with at home. These differences did not affect standardized scores, but the magnitude of the difference was associated with worse emotional regulation. The effects of sleep disturbance during polysomnography, or the influence of poor emotional regulation on sleep in the laboratory, should be considered in studies of young children.

Sleep habits and risk factors for sleep-disordered breathing in infants and young toddlers in Louisville, Kentucky.

INTRODUCTION: Snoring affects biobehavioral development among preschool and early school-age children. The goals of the present study were to survey the parents of a large community sample of infants and young toddlers to evaluate (a) naturalistic sleep duration and location; (b) snoring prevalence; and (c) demographic measures and sleep behaviors related to the presence of snoring either 2 or >or=3 days/week. METHODS: Questionnaires were completed by parents of children ages 2 weeks to 2 years attending well-baby checkups and were also mailed to the homes of six-month-old infants. RESULTS: Data from 944 children were available for analyses. No age differences were reported for total sleep duration, co-sleeping, or snoring. Average daily sleep duration was 12.5+/-1.8h (standard deviation (SD)), with daytime naps accounting for an increased proportion of total sleep duration among younger infants. Co-sleeping was reported by 15% of families. Snoring 2 days/week was reported in 11.8% and> days/week in 5.3% of participants. Survey items indicating risk for sleep-disordered breathing (SDB) clustered into factors related to the child, their environment, and their family; restless sleep was exclusively related to snoring 2 days/week and ethnicity, sweating during sleep, and noisy breathing exclusive to snoring >or=3 days/week. CONCLUSIONS: Young infants appear to sleep less than currently recommended. Co-sleeping is relatively common and not age-dependent through the first 2 years of life. Items relating to the child's sleep behaviors, environment, and parents' perceptions were predictive of positive report of snoring, with snoring rates consistent with a significant risk for SDB being similar to those reported for older children.

Effects of a single night of postpartum sleep on childless women's daytime functioning.

STUDY OBJECTIVES: The maternal postpartum period is characterized by sleep fragmentation, which is associated with daytime impairment, mental health disturbances, and changes in melatonin patterns. In addition to sleep fragmentation, women undergo a complex set of physiological and environmental changes upon entering the postpartum period, confounding our understanding of effects of postpartum sleep disturbance. The primary study aim was to understand the basic impact of a single night of postpartum-like sleep fragmentation on sleep architecture, nocturnal melatonin levels, mood, daytime sleepiness, and neurobehavioral performance. MEASUREMENTS AND RESULTS: For one week prior to entry into the laboratory, eleven healthy nulliparous women kept a stable sleep-wake schedule (verified via actigraphy). Participants contributed three consecutive nights of laboratory overnight polysomnography: (1) a habituation/sleep disorder screening night; (2) a baseline night; and (3) a sleep fragmentation night, when participants were awakened three times for ~30min each. Self-reported sleep quality and mood (Profile of Mood States survey) both decreased significantly after sleep fragmentation compared to baseline measurements. Unexpectedly, daytime sleepiness (Multiple Sleep Latency Test) decreased significantly after sleep fragmentation. Experimental fragmentation had no significant effect on time spent in nocturnal sleep stages, urinary 6-sulfatoxymelatonin concentration, or psychomotor vigilance test performance. Participants continued to provide actigraphy data, and daily PVTs and self-reported sleep quality assessments at home for one week following sleep fragmentation; these assessments did not differ from baseline values. CONCLUSIONS: While there were no changes in measured physiological components of a single night of postpartum-like experimental sleep fragmentation, there were decreases in self-reported measures of mood and sleep quality. Future research should examine the effects of multiple nights of modeling postpartum-like sleep fragmentation on objective measures of sleep and daytime functioning.

Actigraphic recordings in quantification of periodic leg movements during sleep in children.

BACKGROUND: Periodic limb movement disorder (PLMD) has recently emerged as a relatively frequent and markedly underdiagnosed condition in children that induces arousals and sleep fragmentation and leads to poor learning and behavioral problems. Because a cost-effective and widely available alternative to pediatric polysomnography is needed for diagnosis of limb movement disorders, this study sought to examine whether periodic leg movements in children could be reliably identified using recently developed actigraphy software. METHODS: Bilateral actigraphs were worn around the feet by 99 children ages 4-12 years during standard clinical overnight polysomnography, which included bilateral anterior tibial electromyogram (EMG). Left and right leg movements were scored independently for comparison purposes. RESULTS: Agreement between tibial EMG and actigraphy-derived events were initially low, with movement indices being overestimated by actigraphy. This agreement was improved when a correction factor based on the average number of movements during arousals as measured by EMG was applied. However, the correction factor itself was found to differ substantially for patients who were diagnosed with PLMD compared to other patients. CONCLUSIONS: A novel actigraphic approach currently used for detection of PLM events during sleep in adults is insufficiently accurate to permit reliable estimates in children.