Sleep and parenting

Last time, we looked at the transition to parenting. Today, we look at the same period but related to sleep. First, Hoyniac et al. (2023) published “Sleep and Circadian Rhythms during Pregnancy, Social Disadvantage, and Alterations in Brain Development in Neonates” in Developmental Science. Here’s the edited abstract:

Pregnant women in poverty may be especially likely to experience sleep and circadian rhythm disturbances, which may have downstream effects on fetal neurodevelopment. However, the associations between sleep and circadian rhythm disturbances, social disadvantage during pregnancy, and neonatal brain structure remains poorly understood. The current study explored the association between maternal sleep and circadian rhythm disturbances during pregnancy and neonatal brain outcomes, examining sleep and circadian rhythm disturbances as a mediator of the effect of social disadvantage during pregnancy on infant structural brain outcomes. The study included 148 mother-infant dyads, recruited during early pregnancy, who had both actigraphy and neuroimaging data. Mothers’ sleep was assessed throughout their pregnancy using actigraphy, and neonates underwent brain magnetic resonance imaging in the first weeks of life. Neonatal structural brain outcomes included cortical gray matter, subcortical gray matter, and white matter volumes along with a measure of the total surface area of the cortex. Neonates of mothers who experienced greater inter-daily deviations in sleep duration had smaller total cortical gray and white matter volumes and reduced cortical surface areas. Neonates of mothers who had higher levels of circadian misalignment and later sleep timing during pregnancy showed smaller subcortical gray matter volumes. Inter-daily deviations in sleep duration during pregnancy mediated the association between maternal social disadvantage and neonatal structural brain outcomes. Findings highlight the importance of regularity and rhythmicity in sleep schedules during pregnancy and bring to light the role of chronodisruption as a potential mechanism underlying the deleterious neurodevelopmental effects of prenatal adversity.

Research Highlights

1. Social disadvantage was associated with sleep and circadian rhythm disturbances during pregnancy, including later sleep schedules, increased variability in sleep duration, circadian misalignment, and a higher proportion of the sleep period spent awake.

2. Maternal sleep and circadian rhythm disturbances during pregnancy were associated with decreased brain volume and reduced cortical surface area in neonates.

3. Maternal inter-daily deviations in sleep duration during pregnancy mediated the association between social disadvantage and neonatal brain volume and cortical surface area.

This study illustrates the important role of Mom’s sleep in relation to neonatal brain development. The next study looks further at implications of poor sleep. The next study illustrates more adverse impacts of mom getting poor sleep. Leerkes, Negi, Buehler, Shriver & Wideman (2024) published “Interactions between Poor Sleep and Negative Social Cognition Pose Risk for Lower Maternal Sensitivity” in Journal of Family Psychology. Here’s the edited abstract:

The extent to which mother and infant sleep predict maternal sensitivity as (a) main effects and (b) moderate the association between social cognition about infant crying (i.e., cry processing) and maternal sensitivity was examined in a sample of 299 mother–infant dyads (43% of mothers non-White; 50.5% of infants female). Infant- and mother-oriented cry processing were assessed prenatally using a video recall procedure and mothers self-reported demographics and characteristics reflecting emotional risk. When infants were 2 months old, mothers reported their depressive symptoms and mother and infant sleep. Maternal sensitivity and infant negative mood were observed during free play and the still face. There were no main effects of mother or infant sleep on maternal sensitivity over and above covariates. However, infant total sleep duration across night and day and mother sleep disturbance moderated the effect of mother-oriented cry processing on sensitivity. Specifically, mother-oriented cry processing was associated with lower maternal sensitivity only among mothers whose infants had lower sleep duration and who reported more sleep disturbances. Moderating effects were not apparent for infant night wakings or time awake or mothers’ total sleep problems. Constrained opportunities for sleep or respite across the entire day and the totality of mothers’ nighttime sleep disturbances, not just those specific to infants’ night wakings, undermine maternal sensitivity by exacerbating mothers’ preexisting tendency to have self-focused and negative reactions to infant distress. The efficacy of interventions designed to facilitate maternal sensitivity and infant adjustment may be enhanced by adding targeted foci on maternal and infant sleep. 

Here we see that, if both mom and baby are sleeping badly, mom is likely to exhibit less maternal sensitivity. Taken together, these studies illustrate the importance of understanding mom’s social disadvantage and sleep quality in relation to their child’s development.