Your baby was finally sleeping longer stretches. Then suddenly, they are waking every hour, feeding all night, and crying more than usual. You start to wonder is this a growth spurt or a sleep regression?
Both growth spurts and sleep regressions can disrupt your baby’s sleep, but they stem from different causes and often require different responses. Knowing how to distinguish between the two can help you better meet your baby’s needs and maintain your own sanity in the process.
What Is a Growth Spurt?
A growth spurt is a period of rapid physical development when your baby grows in size and gains weight at an accelerated pace. During these phases, babies tend to feed more often and may seem fussier or more restless than usual.
According to the American Academy of Pediatrics, most babies experience noticeable growth spurts at:
- 2 to 3 weeks
- 6 weeks
- 3 months
- 6 months
- 9 months
Each growth spurt typically lasts two to three days, though some can stretch to a week. During that time, your baby may want to cluster feed, especially at night, which can disrupt their sleep. Once the spurt ends, feeding patterns and sleep usually return to baseline (AAP).
What Is a Sleep Regression?
A sleep regression is a developmental phase when a baby who was previously sleeping well begins waking more often, fighting naps, or resisting bedtime. These regressions are usually tied to brain development, increased awareness, or new skills like rolling, crawling, or walking.
Common regression ages include 4 months, 8 to 10 months, 12 months, 18 months, and 24 months. Regressions often last two to six weeks, and the sleep disruption tends to be more persistent than during growth spurts.
Key Differences Between a Growth Spurt and Sleep Regression
While both events disrupt sleep, they show up in different ways. Here is how to tell which one you are facing.
1. Feeding Patterns
Growth Spurt: Babies usually feed more frequently during a growth spurt, both during the day and night. Breastfed babies may nurse for longer stretches or return to cluster feeding.
Sleep Regression: Feeding may or may not increase. If your baby wakes but does not always want to eat, it could point to a regression rather than hunger.
2. Duration
Growth Spurt: Usually lasts just a few days to a week.
Sleep Regression: Often lasts two to six weeks. If the sleep issues continue beyond a few days and are accompanied by new developmental milestones, it is likely a regression.
3. Emotional and Physical Behavior
Growth Spurt: Babies may be extra sleepy or just slightly fussier. Physical growth is the primary focus.
Sleep Regression: Babies tend to be more irritable, clingy, or alert. They may also be learning new skills, such as crawling or babbling, which they often want to practice at bedtime or during night wakings.
4. Developmental Signs
Growth Spurt: Your baby grows noticeably in length, weight, or head circumference. You may find that clothes suddenly do not fit.
Sleep Regression: Your baby shows new skills like rolling over, sitting, pulling to stand, or forming new words. These mental and motor leaps activate the brain and disrupt sleep, even if your baby is physically tired.
5. Response to Soothing
Growth Spurt: Babies are often comforted by extra feeding and cuddles. Once hunger is satisfied, they usually settle.
Sleep Regression: Soothing may be more difficult. Your baby may wake repeatedly without an obvious need or protest being left alone, even after a full feed.
Can They Happen at the Same Time?
Yes, and often they do. It is not uncommon for a baby to go through a growth spurt and sleep regression close together, especially around the four-month mark when sleep cycles begin to mature.
This overlap can make things feel even more chaotic, but it also explains why some babies seem hungrier, fussier, and harder to settle all at once.
How to Support Your Baby Through Either Phase
Whether it is a growth spurt or a sleep regression, your baby needs the same core support: nourishment, comfort, and a safe sleep environment. Here are some strategies that help in both cases:
- Feed on demand: During growth spurts, your baby may need more milk or formula. Let them guide the frequency.
- Watch wake windows: Overstimulation and overtiredness can worsen sleep disruptions. Adjust your routine if needed.
- Create a consistent bedtime routine: Rituals like a warm bath, a short book, and dim lighting help signal sleep.
- Offer physical comfort: Hold, rock, or wear your baby during the day if they are clingier than usual.
- Give it time: Both growth spurts and regressions are temporary, even though they feel endless when you are in them.
When to Call Your Pediatrician
Although most sleep disruptions are temporary, contact your doctor if your baby:
- Is not gaining weight or feeding poorly
- Is unusually lethargic or inconsolable
- Shows signs of illness like fever or rash
- Snores loudly or gasps during sleep
These could be signs of a medical issue, not just a developmental phase.
Final Thoughts: Trust the Patterns
If your baby suddenly stops sleeping well, do not panic. Ask yourself these questions:
- Are they feeding more frequently?
- Are they showing signs of new development?
- Has the disruption lasted more than a few days?
These clues can help you determine whether you are dealing with a growth spurt, a regression, or a bit of both.
No matter the cause, this phase will pass. And by understanding the difference, you can feel more prepared and less overwhelmed when it happens again — because chances are, it will.
To get a clearer picture of what sleep regressions look like across the first two years, explore this comprehensive guide to baby sleep regressions. It can help you know what to expect and how to support your baby gently through each stage.