4 month sleep regression: causes, signs and how to handle it
Is your baby suddenly waking more? Here's what causes the four-month sleep regression, how long it lasts, and expert-backed tips to manage it.
Is your baby four months old and struggling to sleep all of a sudden? Welcome to your first ‘sleep regression.’
Your baby might have been a great sleeper before, easily settled and able to self-soothe. But now, they might wake constantly, cry at bedtime, and refuse to nap. It’s nothing to worry about, just a stage of development commonly called the four-month sleep regression.
This phrase gets thrown around a lot in new parent circles, but it’s not a medical diagnosis. It’s just a popular term used by parents, sleep experts, and health visitors to describe a temporary but very real shift in your baby’s sleep habits.
We spoke to Theresa Ross, a sleep therapist and clinical nurse specialist in paediatric sleep services at Evelina Children's hospital, about what exactly is going on and how you can survive this blip.
What is the four-month sleep regression?
“‘Sleep regression’ is a term used to describe a change in a baby’s sleep pattern, from a previously settled pattern to less settled. They might suddenly start waking more often and struggle to settle to sleep,” Theresa says.
“It does not actually mean that your child’s sleep has regressed,” she says. “If your child is well, think of these changes less as a “regression” and more as a normal stage of infanthood.”
It’s actually the opposite of a regression — it’s a sign of progress as babies grow and their brains develop.
Sleep regressions can happen at any time during childhood (and even adulthood!), and Theresa says there’s “no clinical evidence of specific times a child might expect changes to their sleep pattern.” They do tend to happen around developmental stages, though.
Why does the four-month sleep regression happen?
There are several reasons why the four-month sleep regression occurs. Around this age, babies experience big developmental changes which can make settling to sleep a little more difficult.
They become more aware of their surroundings and so are more attuned to any stimulation around them, especially if there are environmental changes like loud noises or a hot/cold bedroom.
Or, they might be having physical growth spurts that mean they wake up hungry in the night. Illness, teething, or discomfort from immunisations can disrupt sleep at this age, too.
Changes in daily routines, such as holidays, parents returning to work, or starting daycare, can also affect your baby’s sleep.
Signs your baby is going through the four-month sleep regression
Some common ways to know if your baby is experiencing the four-month sleep regression include:
- Waking more frequently during the night
- Struggling to settle to sleep or taking longer to fall asleep
- Becoming more difficult to settle after night wakings
- Increased fussiness or crying at bedtime
- Shorter naps or changes in nap patterns
- Seeming more alert or easily distracted at bedtime
How long does a four-month sleep regression last?
“It’s usually a short-lived change and won’t last too long,” Theresa says.
Your baby will continue to grow and develop, and so they might go through multiple ‘sleep regressions’ before they can sleep through the night — as well as after it.
“Such changes occur throughout childhood for a variety of reasons, just as they do with adult sleep,” Theresa says.
Tips to deal with four-month sleep regression
“Parents need not worry about these changes unless their child is ill,” Theresa says. If your baby is unwell or teething, this may affect their sleeping, so speak to your GP if you’re concerned.
“However, if it continues, you may find yourself falling into settling habits like feeding or rocking them to sleep, that will prolong the changes,” she says. This is because your baby will get used to these cues that it is bedtime and be unable to go to sleep without them.
Here are some other tips on how to get through a sleep regression without resorting to these habits:
- Stick to a consistent bedtime routine. Keeping your baby’s bedtime routine the same each night helps them feel secure and signals that it’s time for sleep.
- Watch for sleep cues. Look for signs that your baby is tired, such as rubbing eyes, fussiness, or staring off into space, and start their bedtime routine then.
- Encourage self-soothing. Try to put your baby down while they are drowsy but still awake, to help them learn to settle themselves.
- Don’t rush in at every sound. Give your baby a few moments to see if they can resettle on their own before intervening — this helps with self-soothing.
- Ensure a calm sleep environment. Keep the bedroom at a comfortable temperature (around 18-19°C), dim the lights, and minimise noise.
- Adjust their feeding schedule if needed. Growth spurts can increase hunger, so your baby may need more frequent feeds during this period, or a larger feed before bed.
- Delay bedtime a little. If your baby just isn’t tired at bedtime, try pushing it back a little to see if they can drop off easier once they are more tired.
- Share the load and make sure you take care of yourself, too. If possible, share night-time care with your partner or family members so you can catch up on some shut-eye and avoid getting too stressed or sleep-deprived.
Most importantly, remember this is just a phase — and like all phases, it will pass. If you stay consistent, offer comfort when needed, and gently encourage healthy sleep habits, you’ll both come through the other side just fine.