Sleep through the night? Babies tend to mix it up

"Parents are often exposed to a lot of contradictory information about infant sleep," says Marie-Hélène Pennestri. (Credit: Getty Images)

Your baby’s ability to sleep through the night is a process, not a milestone, a new study shows.

New parents often expect their baby to start sleeping through the night around the time they reach six months of age.

Tracking 44 infants over a period of two weeks showed that sleeping patterns vary greatly–not only for different babies, but also night-to-night for the same baby.

In the study in the journal Sleep Medicine, researchers asked mothers to keep a sleep diary about their six-month-old infant for two weeks. On average, mothers reported that their infant slept 6 hours consecutively for about 5 nights out of a two-week period, and 8 consecutive hours for about 3 nights out of the same period. Half of the infants, however, never slept 8 hours consecutively.

“Although previous research has shown that infants start sleeping through the night at different stages of development, little is known about individual sleep patterns night after night,” says Marie-Hélène Pennestri, assistant professor in the department of educational and counseling psychology at McGill University and researcher at the Hôpital en santé mentale Rivière-des-Prairies (CIUSSS-NIM).

The researchers also found that some parental practices were related to variability in sleep patterns. For example, breastfeeding and co-sleeping were associated with more variability in sleep patterns night to night. While this finding is consistent with many studies, the researchers note that other factors could explain this occurrence. For instance, mothers who are breastfeeding and co-sleeping are more likely to observe their infant’s night awakenings, even though these awakenings are not necessarily problematic or disturbing.

“Parents are often exposed to a lot of contradictory information about infant sleep. They shouldn’t worry if their baby doesn’t sleep through the night at a specific age because sleep patterns differ a lot in infancy,” says Pennestri. Parents and clinicians should both be aware that occasional sleeping through the night does not necessarily indicate a consolidation of this behavior, she notes.

“One important piece of the puzzle is understanding parents’ perceptions and expectations of infant sleep. In future research, we hope to explore what ‘sleeping through the night’ really means to them,” says Pennestri.

Source: McGill University