Baby sleep requirements

Evidence from a recent, large-scale study of child sleep behavior
Iglowstein and colleagues tracked 493 Swiss children from birth to 16 years (Iglowstein et al 2003). Here are the sleep patterns they observed for children under the age of 2 years. They may serve as a rough guide to baby sleep requirements.

1 month old:

• The average baby got a total of 14-15 hours of sleep

• 50% of babies got between 13 and 16 hours

• 96% of babies got between 9 and 19 hours

3 months old:

• The average baby got a total of 14-15 hours of sleep

• 50% of babies got between 13 and 16 hours

• 96% of babies got between 10 and 19 hours

6 months old:

• the average baby got about 14.2 hours of total sleep

• 50% of babies got between 13 and 15.5 hours

• 96% of babies got between 10.4 and 18.1 hours

9 months old:

• the average baby got about 13.9 hours of total sleep

• 50% of babies got between 12.8 and 15 hours

• 96% of babies got between 10.5 and 17.4 hours

1 year old:

• the average baby got about 13.9 hours of total sleep

• 50% of babies got between 13 and 14.8 hours

• 96% of babies got between 11.4 and 16.5 hours

18 months old:

• the average baby got about 13.6 hours of total sleep

• 50% of babies got between 12.7 and 14.5 hours

• 96% of babies got between 11.1 and 16 hours

2 years old:

• the average baby got about 13.2 hours of total sleep

• 50% of babies got between 12.3 and 14 hours

• 96% of babies got between 10.8 and 15.6 hours

 

These numbers represent total sleep duration—-how much babies slept over a 24-hour period. Of course, not all of this sleep time occurred at night.

One-month-old babies slept an average of 8 hours each night, with 96% of babies getting between 6 and 13.3 hours of nighttime sleep. At 3 months, babies spent more time sleeping at night—-10 hours, on average. For babies over 6 months, the amount of nighttime sleep stayed fairly constant across ages—about 11 hours on average, with a range of approximately 9-13 hours (Iglowstein et al 2003).

Baby sleep requirements are also met by sleeping during the day. Here is some information on the amount of time babies spent taking naps.

Daytime sleep (naps)
 
In the Swiss study (Iglowstein et al 2003), all babies took naps throughout their first year. Most babies continued the practice of napping throughout their second year, with 87% of 2-year olds taking daytime naps. Time spent napping followed these patterns:

1 month old

• the average baby slept between 5 and 6 hours during the daytime

• 50% of babies slept between approximately 4.5 and 7 hours

• 96% of babies slept between 2 and 9 hours

3 months old

• the average baby slept a bit less than 5 hours during the daytime

• 50% of babies slept between approximately 3.5 and 6 hours

• 96% of babies slept between 1 and 8 hours

6 months old

• the average baby slept about 3.4 hours during the daytime

• 50% of babies slept between approximately 2.5 and 4.5 hours

• 96% of babies slept between 0.4 and 6.4 hours

9 months old

• the average baby slept about 2.8 hours during the daytime

• 50% of babies slept between approximately 2 and 4 hours

• 96% of babies slept between 0.2 and 5.3 hours

1 year old

• the average baby slept about 2.4 hours during the daytime

• 50% of babies slept between approximately 2 and 3.5 hours

• 96% of babies slept between 0.2 and 4.6 hours

18 months old

• the average baby slept about 2 hours during the daytime

• 50% of babies slept between approximately 1.5 to 2.5 hours

• 96% of babies slept between 0.5 and 3.6 hours

2 years old

• the average baby slept about 1.8 hours during the daytime

• 50% of babies slept between approximately 1.3 to 2.3 hours

• 96% of babies slept between 0.7 and 2.9 hours

 

Elsewhere, naps may be on the decline. In a recent study of American children, 82% of babies over 18 months were not taking any naps on some or all days (Acebo et al 2005).