Why baby's evening naps make sleep worse for your family

If your baby takes an evening nap, and especially if this becomes a pattern over time, the following things might happen.

• Your baby's bedtime becomes very late.

• Your baby starts to wake excessively at night.

• Your baby begins stirring, groaning or grunting or wanting to feed, from the small hours of the morning.

• Your baby is ready to start the day much too early.

In other words, evening naps (especially if they become a pattern) can seriously disrupt the settings on your baby's body clock, so that her sleep is no longer in sync with your own sleep needs. This is why they are best avoided!

If you have a newborn, his little body clock will still be adjusting to the real world around him, and he may sleep in the evening. If everything else is going well at nights, you don't need to worry. But it is still helpful to know, for the weeks and months that lie ahead, how to keep your baby's body clock settings healthy and how to meet his sensory motor needs.

How can you protect your baby's sleep when you live in a land with very long or very short days, depending on the season?

How can you keep your baby's sleep healthy if you live in a country where the sun sets very late (or even doesn't set at all) in summer? Or where the sun sets very early (or doesn't even rise) in winter?

There are three circadian or environmental cues that keep the settings of your and your baby's body clock healthy: light, noise and activity during the day, contrasting with the dark, and minimal noise and activity during the Big Sleep at night. Light is by far the most powerful environmental cue.

When we live with particularly long or short days, modern humans artificially create the cues of light or dark. If you live in a land that has a midnight sun or a polar night, you already know about creating your own substitute circadian cues, using black-out blinds and eye masks when the clock tells you it's bedtime, or continuing on with usual daytime activities even if there is only brief and dim daylight.

In these parts of the world, parents also actively surround their baby with the other environmental cues of noise and activity during what other countries think of as average daytime hours (even when the sun isn't rising) and less noise and activity during the Big Sleep at night (even when the sun isn't setting).

In these climates, using the clock to help guide our decisions about baby bedtimes becomes a temporary seasonal necessity. In these climates, it is even more important to be aware of how your baby's sleep regulators - the body clock and sleep pressure - work, and how to make changes if a pattern of excessive night waking arises.

Needless to say, human children have taken enough sleep in those latitudes down the millennia, without any harm to their development.