Breastfeeding linked to more night awakenings but longer sleep duration in infants

Fully breastfed infants have more night awakening but longer night- and total-sleep durations overall than those fed with formula, a study has shown.

This study included 654 caregivers of naturally conceived, term, singleton infants who completed the Brief Infant Sleep Questionnaire (3, 6, 9, 12, 18, and 24 mo) and/or Children's Sleep Habits Questionnaire (54 mo), and provided information on their infants’ breastfeeding status at 3 mo.

In trajectory analyses, the investigators derived 4 day- (n=243), 3 night- (n=248), and/or 4 total- (n=241) sleep trajectories, each differing in length of sleep duration (short/moderate/long) and variability (variable/consistent). They also assessed associations between breastfeeding and sleep-wake behaviours from 3–14 mo (day/night/total-sleep durations and duration/number of night awakenings).

After adjusting for potential covariates, formula-fed infants were less likely to exhibit moderate (odds ratio [OR], 0.28, 95 percent confidence interval [CI], 0.11–0.70) and long consistent (OR, 0.18, 95 percent CI, 0.07–0.50) night-sleep trajectories and less likely show moderate (OR, 0.21, 95 percent CI, 0.07–0.61) and long consistent (OR, 0.12, 95 percent CI, 0.04–0.38) and long variable (OR, 0.16, 95 percent CI, 0.05–0.56) total-sleep trajectories, rather than short variable night- and total-sleep trajectories, as compared with fully breastfed (predominant or exclusive) infants.

Partially breastfed were no different from fully breastfed infants in terms of both night- and total-sleep trajectories. There were also no significant differences noted between all groups for day-sleep trajectories. In addition, fully breastfed infants had longer night- (6, 9, 12, and 12 mo) and total- (3 and 12 mo) sleep durations than formula-fed counterparts, although they showed a greater number of night awakenings (from 6 to 12 mo).