Some of you may feel that your baby or toddler doesn't need a lot of sleep. Or "How is it possible they need 14 hours of sleep?" It's because when we sleep that's when our bodies restore themselves. So you can see why a baby needs so much sleep! They are growing and learning so much that their sleep is so important to be able to keep up with it all. You may have heard about REM sleep which stands for Rapid Eye Movement, and Non-REM sleep. Everyone goes through these two types of sleep. Within these two types of sleep there are 5 stages. Non-REM sleep has 4 stages and REM sleep has 1 stage.
What are the 5 stages? STAGE 1(Non-REM) - Very light sleep. This is when a baby appears to be drowsy, but has already started to doze off. STAGE 2 (Non-REM) - Light sleep. A baby still can be woken very easily during this stage. STAGE 3 (Non-REM) - Deep sleep. Not yet the deepest sleep but at the beginnings of a deep sleep. If you were to wake a baby at this stage they would be quite groggy and confused. STAGE 4 (Non-REM) - Deepest sleep. This is the stage that your baby's body restores itself the most. This is also when nightmares can take place. STAGE 5 (REM) - This is when dreaming takes place. You are again in a lighter sleep but your brain is very active. We cycle through these stages many times during a night. Adults will spend 75% of their sleep in Non-REM sleep and 25% of it in REM sleep during a 90 minute cycle that happens about 4-6 times a night. Babies will spend about 50% of their sleep in both Non-REM and REM sleep and their cycle is about 30-50 minutes long. By 6 months of age babies will spend 30% of their sleep in REM sleep, and their cycle starts to get longer and closer to 90 minutes by preschool. So you may wonder why your baby only naps for 30-50 minutes? If they don't know how to get themselves back to sleep, then when they naturally wake up from their first cycle they will want to get up or else you to come put them back to sleep. Same goes for the night. If you find yourself getting up very frequently in the night it's because your baby hasn't learned how to put themselves back to sleep after a sleep cycle. Often people will say their baby slept so well for the first 5 hours and then after that they were up every hour needing help to get back to sleep. This is because in the first cycle, REM sleep is the shortest part of the cycle. But the closer morning gets the more time your baby spends in REM sleep. If your baby doesn't know how to put their self back to sleep, they will awaken more frequently during this time wanting to be put back to sleep. You can also see how your baby can be easily woken in the mornings by light noises and have a hard time getting back to sleep. If you find yourself rocking your baby to sleep or holding them until they fall asleep, you may notice that you need to continue to do it for roughly 20 minutes before you can lay them in their crib. That is because it takes a baby about 20 minutes to get into a deep sleep. Then they may only sleep for another 30 minutes (a sleep cycle) because they need your help to get back to sleep. Some parents don't have a problem with doing this and love to rock their babies to sleep. For myself I found it exhausting and I never got anything done or any time to myself. But there is more to it then that. A baby that has poor sleep habits can result in many things: - crankiness, clinginess, tantrums - as I've mentioned in my previous post - harder to get through milestones and teething - increase in maternal depression - baby isn't sleeping so Mommy isn't sleeping - lack of physical growth - body isn't able to restore itself properly - "Children aged four and under who get less than 10 hours of sleep a night are nearly twice as likely to be overweight or obese five years later, according to a U.S. study." quoted from reuters.com So you can see that sleep is very important! I hope you find this as interesting as I do and maybe will help you with a few of your baby's sleep problems. If you have further questions feel free to email me! Here are a few charts that help summarize what I was explaining.