If you have not already done so, please read Blog Posts 1 through 5 that describe how sleep is important and beneficial. I will post specific information for parents and children based on my book, “Healthy Sleep Habits, Happy Child.” Please do not be put off by my book’s length. This is a reference book. Read only the topic of interest to you.
This is my opinion, based on my general clinical pediatric practice over 40 years, my many sleep consultations, my own research, and reviewing published scientific papers. Additionally, data shows that there is a long-standing trend towards later bedtimes that causes a decrease in total sleep duration. As more and more infants and children become short on sleep, they have more difficulties falling asleep and staying asleep. Here is the data:
Bedtimes have become later and later. This trend began a long time ago. Here are data showing bedtime (PM) by age:
The trend towards later bedtimes means that the total sleep duration has decreased. Here are data showing total sleep duration (hours) by age:
Data specific for Spain shows the same trend towards decreased total sleep duration (hours) over time:
As described in Blog Post 6, small differences in sleep duration can produce major consequences over time.
My published research, in 1982, shows that moving the bedtime to an earlier hour dramatically reduces the number of night wakings and the time interval between being put down to sleep and actually falling asleep (sleep latency). To accomplish the earlier bedtime, the parents woke her every morning at 7AM and did not permit afternoon naps. This tactic of ‘controlling the wake-up time’ has mostly been discussed in the adult literature in the context of ‘chronotherapy’, that is, resetting the circadian clock. Although this tactic is effective, it is not well known in pediatrics. For example, my paper has been cited only once, in 1993.
In 1999, a study of children 2 to 5 years of age showed that the later bedtimes were associated with shorter night sleep duration. Less sleep at night was associated with behavior problems even when short night sleep is associated with longer and more frequent naps such that 24-hour sleep duration is normal.
In a 2020 study, objective measurements, using sleep actigraphs at 6, 15, and 24 weeks showed that “Infants who fell asleep earlier also slept longer at night. Keeping infants up later in hopes of them sleeping in longer may be counterproductive.”
A separate study in 2020, using objective measurements, found that at 3, 6, and 13 months, “that infants with later sleep times had less nighttime sleep.” They did not wake up later.
So, no matter your child’s age, when you consider early bedtimes (Blog Posts 7 and 22) and use drowsy signs (Blog Post 9), don’t be shocked if your child goes to bed much earlier than your friends’ children. Their late bedtimes might be very common but being common is not the same as being healthy. Today, commonly occurring bedtimes might be too late, and unhealthy, for most children.