Sleep regressions come at predictable times because they are a by-product of your baby’s development. And during your baby’s 4th month, he goes through several developments which can worsen his sleep.
Here are the 3 big causes of the 4 month sleep regression.
Cause #1: Your baby’s brain matures
During your baby’s fourth month, his brain goes through a big developmental shift. Part of this shift changes his sleep patterns. Your baby may become harder to settle for sleep or sleep shorter stretches.
Also, your little one is becoming more aware of his world. He wants to interact, play and smile. It can be harder for him to relax and fall asleep in a noisy room, like he did as a newborn.
Because this regression is a result of normal brain development, it’s a good thing! Some parents wonder if the 4 month sleep regression is a myth because not every baby seems to experience it.
It’s important to know that all babies will pass through this brain development, but not all of them will have outward signs of a sleep regression. (If this is you, consider yourself lucky. And go buy a lottery ticket!)
Cause #2: Your baby has a growth spurt
Your little one is growing at a tremendous pace during his first year. Growth spurts are par for the course with growing babies. There will be periods of time when you notice that your baby seems hungry all the time. The fourth month is one of those times.
If your 4 month-old is waking up more often at night to feed, he could be going through a growth spurt. Feed him if he’s hungry.
Make sure to prioritize his daytime nutrition too. Offer him a feed every 2 hours during the day. Filling up his tank during the day can help him go longer at night between feeds. Growth spurts are temporary, and usually pass within a few days.
Cause #3: Your baby wants to drop the 4th nap
This won’t apply to all babies, but it’s worth mentioning. As your infant grows, he’ll be able to stay awake longer during the day. And if some of his naps are long, he may not have time to fit in a fourth nap each day.
Many (but not all) babies will want to transition from 4 to 3 naps around this age. Nap transitions can be tricky and unintentionally lead to long awake times during the day, which can over-tire your baby. Over-tiredness can worsen night sleep, and make baby harder to settle and wake more often. And then we have a vicious cycle…
As long as you watch your 4 month-old’s awake times, and have him nap every 1.5 – 2.5 hours, you’ll be ok. Your baby will naturally drop his 4th nap whenever he’s ready and his night sleep shouldn’t suffer.