- Transistions: The sleep cycle is 45 minutes. Some babies who wake at 45 minutes are doing so because it is a transition time. They either are unable to put themselves to sleep alone, or an external factor rouses them to full alertness. This can be temperature, noises, or even (and especially in the newborn months) hunger. See also: Baby Whisperer: Sleep Transitions , Naps: Troubleshooting , and Baby Whisperer: Sensible Sleep
- Overtiredness: If your baby was awake too long before her nap, she likely will not sleep longer than 45 minutes. Hogg states that she might not even last the 45 minutes. See also: Optimal Waketime Lengths , Baby Whisperer: Sleep Cues , Nap Cues , Sleep Begets Sleep , Easy Nap Fix
- Overstimulation: You baby can also wake at 45 minutes if she was overstimulated during waketime. With the newborn, you need to guard her waketime activities closely. As she gets older, she needs more stimulation. Hogg says that you need to have a bedtime/naptime routine. You can't just pick baby up and put her in bed. Hogg says that the routine will help baby wind down and sleep better. See also: Overstimulation , and Sleep Routine .