A sleep regression is a popular, non-medical term for a period when a baby who was sleeping well temporarily starts waking more, resisting naps or struggling to fall asleep. It is usually linked to a new skill, an illness or a change in routine and settles within a few days.
Key takeaways
- Sleep regression is not a medical diagnosis, and not every baby goes through one.
- It is often linked to a new skill, an illness or a change in routine.
- Disrupted sleep usually settles within a few days.
Why does it happen?
Most sleep regressions are linked to a new skill, an illness or a change in routine. A baby who is learning to roll, crawl or pull to stand may want to practise at night too, and teething, a cold, separation anxiety, travel, starting daycare or dropping a nap can also unsettle sleep for a while. According to Yale New Haven Health, sleep regressions are not well defined in the medical literature, and sometimes there is no clear cause at all.
At what ages is it talked about?
Sleep regressions are most often mentioned at around 4, 8-10, 12 and 18 months and at 2 years. These ages line up with big developmental changes, but they are not a timetable: many babies pass them with no change in sleep, and others have a rough patch at a different time.
| Age often mentioned | What may be going on |
|---|---|
| Around 4 months | Sleep becomes more adult-like, with clearer sleep stages and more brief wakings between cycles; rolling may begin. |
| 8-10 months | Crawling, pulling to stand and separation anxiety. |
| Around 12 months | First steps; some babies start to resist their second nap. |
| Around 18 months | Rapid language growth, a stronger wish for independence and a return of separation anxiety. |
| Around 2 years | Bedtime protests, nap changes, new fears, or big changes such as a new bed or a new sibling. |
How long does it last?
A sleep regression usually lasts a few days. Yale New Haven Health advises seeing a pediatrician if sleep problems go on for longer than a few days, as a routine that no longer suits the baby's age or a health issue may be behind it.
What you can do
- Check first for discomfort such as fever, a blocked nose, constipation or ear pain.
- Keep your usual bedtime routine and avoid big changes during this time.
- Give your baby plenty of daytime practice with new skills like rolling and standing.
- Check that naps and awake times still suit your baby's age.
- Offering your baby extra comfort during this time is fine.
When to talk to your doctor
If the sleep problem lasts more than a few days without improving; if your baby snores, pauses in breathing or breathes through the mouth during sleep; if there is fever or signs of pain; or if your baby has lost a skill they had during the day.
Frequently asked questions
No. Changes in sleep are common, but there is no regression that every baby goes through at a set age.
Sleep genuinely matures around this age and some babies wake more often, but it is a normal developmental change rather than a medical condition that affects every baby.
Not for a few days of disrupted sleep; if the problem persists, you can talk to your doctor about options that suit your family.