Sleep patterns and intraindividual sleep variability in mothers and fathers at 6 months postpartum: a population-based, cross-sectional study.

OBJECTIVES: Given that postpartum sleep is an important family process, further investigations including both mothers and fathers are necessary. The present study aimed to describe and compare sleep patterns and intraindividual night-to-night variability in mothers and fathers at 6 months postpartum using subjective and objective sleep measures. DESIGN: Cross-sectional study. SETTING: General community-based study in Montreal, QC, Canada. PARTICIPANTS: Thirty-three couples (mothers and fathers) with no self-reported history of medical and mental health conditions participated in this study. RESULTS: Parental sleep was measured across 10 consecutive nights using both a daily sleep diary and actigraphy. Results demonstrated that mothers' subjective and objective sleep was more fragmented compared with fathers (shorter longest consecutive sleep duration and more nocturnal awakenings; p<0.001). While mothers and fathers did not differ in their self-reported nocturnal sleep duration (p>0.05), actigraphy indicated that mothers obtained significantly longer nocturnal sleep duration (448.07 min±36.49 min) than fathers (400.96 min±45.42 min; p<0.001). Intraindividual sleep variability was revealed by relatively high coefficients of variation for parents across both subjective and objective indices related to sleep fragmentation (between 0.25 and 1.32). Actigraphy also demonstrated variability by mothers sleeping 6 hours consecutively on less than 3 nights, 27.27% (±22.81), and fathers on less than 6 nights, 57.27% (±24.53), out of 10. Associations were also found between parental sleep and family factors, such as age and infant sleep location (p<0.05). CONCLUSIONS: These findings advance our knowledge of how sleep unfolds within the family system beyond the early postpartum weeks and/or months. Given the link between disturbed sleep and family functioning, the current research accentuates the importance of examining postpartum sleep patterns and variability in parents.

Investigating the link between sleep and postpartum depression in fathers utilizing subjective and objective sleep measures.

BACKGROUND: While fathers are at risk of developing poorer sleep and depressive symptoms in the postpartum period, they represent an understudied population in the literature. The present study aimed to explore the association between sleep and postpartum depressive symptoms in fathers using subjective and objective sleep measures. METHODS: Fifty-four fathers reporting no history of depression took part in this cross-sectional study. At 6 months postpartum, paternal sleep was assessed for 2 weeks utilizing a self-report daily sleep diary, a self-report perceived sleep quality rating, and actigraphy. In the same period, depressive symptoms in fathers were assessed with the Center for Epidemiologic Studies-Depression Scale (CES-D). RESULTS: Regression analyses showed that paternal subjective sleep variables captured by the sleep diary (total nocturnal sleep time and number of night awakenings) were not related to postpartum depressive symptoms. However, self-reported perceived sleep quality was significantly associated with postpartum depressive symptom severity in fathers independently of demographic variables related to depression. Alternatively, the objective sleep variables (total nocturnal sleep time, number of night awakenings, sleep efficiency, and wake after sleep onset), measured by actigraphy, did not demonstrate a significant relationship with paternal depression scores. CONCLUSIONS: These findings highlight the importance of perceived sleep quality, along with better understanding its association with postpartum depressive symptoms. Implementing a multi-measure approach enabled us to expand our knowledge about how different facets of sleep relate to postpartum depression, specifically in fathers. The results have important implications for the development of clinical interventions targeting paternal sleep and mood in the postpartum period.

Perception of infant sleep problems: the role of negative affectivity and maternal depression.

STUDY OBJECTIVES: To investigate whether the interaction between infant negative affectivity and maternal depressive symptoms is associated with the degree to which mothers perceive infant sleep to be problematic at 6 months postpartum, independent of infant sleep and sociodemographic factors. METHODS: Infant negative affectivity and maternal depressive symptoms were assessed in a sample of 59 mother-infant dyads at 6 months postpartum using standardized measures. Mothers reported the degree to which they perceived their infant's sleep to be problematic via an item composite of the Sleep Practices Questionnaire. Nocturnal infant sleep variables (duration, number of awakenings) were retrieved from a 2-week infant sleep diary (maternal report). RESULTS: There was a significant interaction between infant negative affectivity and maternal depressive symptoms in predicting mothers' perceived extent of infant sleep problems. Simple slope analysis showed that high levels of depression were related to higher maternal perception of infant sleep problem scores only among mothers of infants with high levels of negative affectivity. Moreover, infant negative affectivity and maternal depressive symptoms positively predicted perception scores after adjustment for infant sleep, maternal age, and parity (P < .05). CONCLUSIONS: The current study provides evidence that high levels of maternal depression combined with high levels of infant negative affectivity may contribute to mothers' perceptions of infant sleep problems, independent of infant sleep duration and awakenings. These findings highlight the importance for pediatricians and other health professionals to consider infant temperament in conjunction with mothers' depressive symptoms when addressing mothers' concerns about infant sleep problems.

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.

Sleeping through the night or through the nights?

OBJECTIVE: There are substantial inter-individual differences in infants' longest consecutive sleep duration. However, intra-individual differences are rarely considered. The present study aimed to describe night-to-night variability in achieving 6 or 8 h of consolidated sleep over a 13-night period in 6-month-old infants. METHODS: Forty-four typically developing infants were part of the study (22 girls). When infants were 6 months old, mothers were asked to complete an infant sleep diary over 13 nights to measure the longest period of uninterrupted sleep each night. Two criteria were used to determine if infants were sleeping through the night: 6 and 8 h of uninterrupted sleep. RESULTS: On average, mothers reported that their infant slept 6 h consecutively for about 5 nights out of 13. Nine infants (20.5%) never slept 6 h consecutively, three (6.8%) met the criterion every night, but most infants (n = 32; 72.7%) showed high variability between the nights. Mothers reported that their infant slept 8 h consecutively for about 3 nights out of 13. Half of the infants (50.0%) never slept 8 h consecutively, one infant (2.3%) slept 8 h consecutively every night, and twenty-one infants (47.7%) showed high variability. CONCLUSIONS: These findings expand current knowledge by showing that there is not only high inter-individual variability, but also high intra-individual variability in infant sleep consolidation. Parents and clinicians should be aware that occasional sleeping through the night does not necessarily indicate a consolidation of this behavior.