The ‘circadian rhythm’ is the 24 hour internal clock that controls various biological processes, including sleep, wakefulness, and digestive and hormonal activity. The natural signal for the circadian pattern is the change from darkness to light.
Unfortunately, a newborn baby has no idea that people are supposed to sleep when it’s dark and his circadian rhythm is still developing. In the first weeks and months therefore, it is unreasonable to expect him to sleep through the night. After a few months however, babies start to synchronize sleeping and waking with daily cycles of darkness and light.
By the time he is six months, your baby will probably be synchronizing his main sleep times with the cycles of darkness and light. He will be sleeping for longer hours at night and probably wake up fewer times. He will also be much better at soothing himself when he wakes. At six months he will be much more likely to be able to go back to sleep on his own, without your help
Talaris Research Institute (2007) “Goodnight Baby” Available from: http://www.talaris.org/spotlight_goodnight.htm (10/10/2009)
Goodlin-Jones, B. L., Burnham, M. M., Gaylor, E. E., & Anders, T. F. (2001). “Night waking, sleep-wake organization, and self-soothing in the first year of life.” Developmental and Behavioral Pediatrics, 22(4), 226-233.
Anders, T. F., Goodlin-Jones, B. L., & Sadeh, A. (1999). Sleep disorders. In C. H. Zeanah (Ed.), Handbook of Infant Mental Health (pp. 326-338). New York: Guilford Press.
(Anders et al., 1999).
Louis, J., Cannard, C., Bastuji, H., & Challamel, M.-J. (1997). Sleep ontogenesis revisited: A longitudinal 24-hour home polygraphic study on 15 normal infants during the first two years of life. Sleep, 20(5), 323-333.