Why will my baby only sleep for 30-40 minutes at a time?

As humans we have an internal body clock know as our circadian rhythm. This clock regulates when we sleep and when we are awake. Babies circadian rhythms don’t start to develop until they are about 12-14 weeks old. What this means is a new-born baby’s internal body clock does not know that its day or night, and therefore tend to sleep the same amount in the day as they do at night. Once they reach 14 weeks old, their circadian rhythm should be well on its way to becoming established.

For babies their sleep cycle is about 40-50 minutes long. The first phase of the cycle is a light phase, which lasts for about 10-15 minutes, they will then enter a deep phase for about 20 minutes, transitioning into another light sleep phase for the last 10-15 minutes. Babies and infants are easily woken during the last phase of their sleep cycle and that is why your baby will only sleep for 30-40 minutes. The trick is to get your baby to transit from one sleep cycle to the next, that’s where I come in.