She should stop waking on her own and instead wait for her parent, who has become her alarm clock. 3. As you add 15-minute increments between wakings, she learns to sleep for longer periods of time. Eventually you phase out the wakings altogether and find that your baby is sleeping through the night.
Usually, REM sleep happens 90 minutes after you fall asleep. The first period of REM typically lasts 10 minutes. Each of your later REM stages gets longer, and the final one may last up to an hour. Your heart rate and breathing quickens. You can have intense dreams during REM sleep, since your brain is more active. Babies can spend up to 50% of their sleep in the REM stage, compared to only about 20% for adults.
Updated December 16, 2014. There are five phases of sleep: stages 1, 2, 3, 4 and REM (rapid eye movement). Usually when you are sleeping, you begin at stage 1 and go through each stage until reaching REM sleep, and then you begin the cycle again. Each complete sleep cycle takes from 90 to 110 minutes. Your brain acts differently in each stage of sleep. In some of the stages, your body may make movements, but in others your arms and legs will be immobile. Having good sleep habits will make sure you get each type of sleep that you need.