The 4-Month Sleep Regression is brutal, but with a little bit of knowledge under your belt, you can help your baby through it.
Baby sleep over the first year is full of ups and downs. There are many factors that disturb an infant's sleep process, such as teething, gas, or overstimulation, and therefore sleep troubles can arise unpredictably. However, there are also several predictable regressions that most babies experience. On the whole, these regressions pass and an exhausted mom needs just to push through. This is not so with the 4-Month Sleep Regression. This regression is in a completely different category than the others and the bad news is, it can't be simply waited out. The good news is, there are a few simple things a mom can do to help her baby sleep well again.
The first thing that you need to know about the 4-Month Sleep Regression is, well, it's not really a regression. Some call it a "progression" instead, to help identify it as different than a mere hiccup in a baby's sleep journey.
You see, when a baby is born, he doesn't experience sleep cycles like adults do. Adults cycle in and out of deep and light sleep repeatedly throughout the night. An infant simply falls immediately into deep sleep and stays there until he's awoken by a need, frequently hunger. That's why it seems they can sleep through anything.
Around 3.5-4.5 months, an infant develops mature sleep cycles like adults. He begins to cycle through deep and light sleep, and when he enters into light sleep, he wakes up and cries. A full sleep cycle lasts 35-50 minutes, and some babies will wake in a panic at every cycle. Often naps will end after one cycle and babies will wake up more often throughout the night, not necessarily needing a feed.
Since the 4-Month Sleep Regression is actually a change in how sleep operates, it doesn't go away on its own. The development of sleep cycles is permanent. Parents need to be proactive in helping their baby learn to sleep at this point, but there are many styles to choose from. Some parents will want to work on getting their child to bed wide awake, as opposed to drowsy or already asleep, so they wake up in the same place that they fell asleep and therefore won't be frightened. Others may choose to use methods other than nursing or bottle feeding at night wakings, so baby's metabolism doesn't adjust to many feeds per night. Parents who are comfortable with sleep training might use training methods like fading, controlled crying, or pick up/put down.
There are a variety of approaches to pick from. The main thing parents should be aware of, is that after this regression, they are teaching their baby something about sleep with their responses, whether they intend to or not.