Many parents wonder how much sleep their baby or child should be getting each day or night, but few ask me how long their baby or child should be awake before needing more sleep (at least, at first!) I call this the “Awake-Time-Threshold.” As a baby grows, his or her Awake-Time-Threshold gets longer and longer, but if a baby is pushed beyond this threshold, sleep-debt and an overtired state can occur, making restorative sleep harder to achieve.

Why is it difficult to put an overtired baby to bed?

When your little one passes into overtiredness, his or her body compensates by releasing hormones to help him stay awake. These hormones (adrenaline and cortisol, mainly) are the body’s way of saying, “There’s no sleep in sight? Ok…here’s a boost for you!” These are the same hormones that helped us pull an all-nighter in college. Unfortunately, these hormones can stick around for up to 8 hours. Even if baby goes to sleep, the chances of him waking frequently and spending less and less time in deep, restorative sleep are high.

These hormones are also why “sleep when the baby sleeps” is impossible advice for some moms to follow–their bodies are coping with chronic overtiredness, so even when they do sleep, it’s not entirely restful.  You can see how easily sleep-debt can accrue.

I also love thinking about Awake-Time Thresholds as a way to minimize crying at sleep-times. An overtired baby will cry…a lot more than a rested one…at bedtime. If you want to teach your baby sleep skills, but don’t want them to be upset while they learn, Awake-Time thresholds are absolutely essential to pay attention to.

Knowing that your baby will need sleep after being awake for their given threshold can help you plan for their sleep and help your baby stay on top of their rest…making sleep easier everyone!