Reference values and changes in infant sleep–wake behaviour during the first 12 months of life: a systematic review

Abstract

This paper is a systematic review on the reference values and changes in infant sleep-wake behaviour during the first 12 months of life. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Seventy-four papers were included, and the reference values and changes in sleep-wake behaviour during the first 12 months of life were identified. Sleep duration during the 24-h period, and day and sleep periods during the night decreased over the first 12 months of life. Night wakings and bedtime/sleep-onset time decreased, while the longest sleep period increased at night during the first 6 months. High discrepancy was noted between studies in the reference values of sleep-wake behaviour, while more congruence was noted regarding changes, especially those occurring in the first 6 months of life. Several methodological differences were identified between studies and may partially explain inconsistencies in the results, including the assessment of different sleep-wake behaviours, the focus on specific ages or age ranges, the use of self-report, observational or direct measures, the recruitment of small or large representative samples, and the countries where the research was conducted. These aspects should be considered in future research and caution should be taken when generalizing results from studies with diverse methodological characteristics. Nonetheless, this review identifies normative reference values and the changes occurring in infant sleep-wake behaviour, and could inform both practitioners and researchers, helping them identify infants with sleep delays or problems.

Sleep habits and sleep characteristics at age one year in the ELFE birth cohort study

“…These latter studies from England [5], European countries (excluding France) [31] and the United States [32] as well as a systematic review [30] reported total sleep durations between 12h40min and 13h/24h at about age 1 year, so French parents report that their infants sleep 30-60min/24h more than their counterparts in developed countries. In a recent literature review of sleep in the first 12 months of life, sleep duration per 24 h tended to be longer in European countries than in the United States, New Zealand, Israel and China [33]. In the current study, this difference seems to be mainly due to longer nap duration in French children but similar nightsleep duration as their peers.…”

Physical activity and objectively assessed sleep in 6‐month‐old infants in Taiwan

“…Infants spent an average of 47.50% of their waking hours engaged in screen‐time‐or‐limited physical activity and a substantial fraction (35.5%) of infants in our study engaged in some screen‐based sedentary behavior. In our study, infant daily hours of sleep were inversely related to diary‐derived screen‐time‐or‐limited physical activity, and the amount of daily sleep (10.85 hr), was similar to the 10.4 hr reported for infants 6 months of age in a systematic review (Dias et al, ). This finding suggests that reducing screen‐time‐or‐limited physical activity, including television viewing and screen time, may improve infant sleep.…”

“…These variables were chosen because they encompass clinically important dimensions of physical activity as well as sleep quantity and quality in young children. These variables have also been reported in prior pediatric research, which facilitates the interpretation of our results (Dias et al, ; Williams et al, ).…”

“…Infancy is a developmental stage during which many major changes are occurring in sleep patterns and physical activity (Dias, Figueiredo, Rocha, & Field, ; Henderson, France, & Blampied, ). Research on physical activity and sleep in pediatric populations is scarce with a strong reliance on the use of parental‐recall questionnaires and survey methods (Foti, Eaton, Lowry, & McKnight‐Ely, ; Thompson & Christakis, ; Wells et al, ).…”

Appropriate age range for introduction of complementary feeding into an infant's diet

“…The Panel notes that the observed differences in sleep duration or night wakings in the RCT by Perkin et al. () were small in relation to an overall night time sleep duration of around 10–11 h at 6 months of age (Dias et al., ) and that the severity of sleep problems was based on the perception of the parents. The Panel considers that the results on these three endpoints are unlikely to be of biological relevance.…”