When do growth spurts happen?

They are commonly noticed around two to three weeks, six weeks, three months and six months. These are rough markers rather than a schedule; many babies spurt at other times or show no obvious spurt at all. Premature babies tend to follow their corrected age more closely than their birth date.

How long does a growth spurt last?

Usually two to three days, sometimes up to a week. If a baby is still feeding far more than usual after a week, or seems unwell, it is worth a check with your health visitor or GP rather than assuming it is still a spurt.

Does a growth spurt mean I do not have enough milk?

Not usually. More frequent feeding is how breastfeeding works: milk production responds to how often milk is removed, so a few days of extra feeding is what raises supply to meet a bigger baby's needs. Signs of enough milk are plenty of wet and dirty nappies and steady weight gain.

Should I give more formula during a growth spurt?

Follow your baby's hunger cues. If they finish bottles quickly and still seem hungry, offering a little more is reasonable. Paced bottle feeding helps them stop when full rather than finishing on autopilot. If you are unsure about amounts, your health visitor can advise.

Do twins have growth spurts at the same time?

Often not. Twins grow at their own pace, and one may be in the middle of a spurt while the other is feeding normally. That can make it feel like one baby is always hungry. Logging each baby's feeds separately usually makes it clear which one it is.

How do I tell a growth spurt from illness?

A growth spurt is a hungry, fussy, otherwise well baby. Illness tends to look different: feeding less rather than more, fewer wet nappies, fever, vomiting, unusual sleepiness or a cry that sounds wrong. If you see any of those, get medical advice rather than waiting it out.

Baby growth spurts: signs and timing

Baby growth spurts: signs, timing, and feeding two at once

Amara Sep 24, 2026 6 min read

Quick answer

A growth spurt is a few days, usually two or three, when a baby suddenly feeds far more often, is fussier than usual and may sleep in shorter bursts. Parents commonly notice them around two to three weeks, six weeks, three months and six months, though the timing varies and plenty of babies do not follow it. Breastfed babies feeding more often is how milk supply rises to meet the new demand, so the answer is to feed on cue rather than stretch feeds out. Formula-fed babies may simply want a little more. If the extra hunger lasts more than about a week, or comes with signs of illness or few wet nappies, check with your health visitor or GP.

For weeks you have had something like a rhythm. Then one morning the baby wants to feed, and feed again an hour later, and again forty minutes after that. They are fussy between feeds, they wake more at night, and you start doing sums about whether something has gone wrong with your milk or the formula or the baby.

Usually what has happened is a growth spurt, and it will probably be over in a couple of days.

What a growth spurt looks like

The signs are consistent enough to recognise:

Much more frequent feeding, sometimes wanting to feed every hour or less, often clustered in the evening
Fussiness between feeds, and sometimes during them
Shorter or more broken sleep, including a baby who had been doing longer night stretches suddenly waking again
Seeming unsatisfied after a feed that would normally have been plenty

What is not part of it: fever, vomiting, a baby who is feeding less, or a noticeable drop in wet nappies. Those are signs of something else.

When they tend to happen

Parents most often notice them around:

two to three weeks
six weeks
three months
six months

Treat these as rough landmarks, not a timetable. Plenty of babies have spurts at other times, some have them more often, and some never have one you could point to. If your baby was premature, their corrected age is a better guide than their birthday.

Why feeding more is the point

This is the part worth understanding, because it takes most of the worry out.

Breast milk works on supply and demand. The more often milk is removed, the more is made. So when a baby suddenly needs more, the way their body asks for it is to feed more often for a few days. That extra feeding is what raises your supply to match. It is not a sign the supply has failed; it is how the supply grows.

The practical upshot is simple: feed on cue. Trying to stretch feeds out, or topping up with formula because you assume the milk has run out, can work against what the baby is trying to do. After two or three days the frequency usually drops back to normal, now at a slightly higher level.

For formula-fed babies it is simpler still. They may want a little more at each feed, or an extra feed, for a while. Follow their cues, and use paced bottle feeding so they can stop when they are full instead of finishing on autopilot.

With twins, it rarely happens in sync

This catches a lot of twin parents out. You might expect both babies to spurt at the same time. Often they do not. Twins grow at their own pace, and it is common for one to be in a spurt while the other is feeding exactly as usual.

From the inside, that can feel like permanent chaos: somebody always seems starving. Keeping a separate record for each baby usually clears it up quickly. A two-day jump in one baby's feeds, with the other steady, is a growth spurt. A jump in both, or a jump that does not come back down, is worth looking at more closely.

If you are breastfeeding twins, spurts are where tandem feeding earns its keep. Feeding both at once halves the number of sessions on the worst days, and a spurting twin feeding alongside a steady one does no harm to either.

Look after yourself through it too. Feeding a spurting baby is hungry, thirsty work. Keep water and food within reach of wherever you feed, and let someone else do everything that is not feeding for those few days.

When to check with someone

A growth spurt is a well, hungry baby. Talk to your health visitor, midwife or GP if:

the extra feeding goes on for more than about a week
there are fewer wet or dirty nappies than usual
your baby is feeding less, not more, or seems unusually sleepy
there is a fever, vomiting, or anything that feels off to you

Weight gain over time, plotted on their growth chart, tells you far more than any single day of feeding. If your baby is following their curve, a hungry couple of days is almost always exactly what it looks like.

Frequently asked questions

When do growth spurts happen?: They are commonly noticed around two to three weeks, six weeks, three months and six months. These are rough markers rather than a schedule; many babies spurt at other times or show no obvious spurt at all. Premature babies tend to follow their corrected age more closely than their birth date.
How long does a growth spurt last?: Usually two to three days, sometimes up to a week. If a baby is still feeding far more than usual after a week, or seems unwell, it is worth a check with your health visitor or GP rather than assuming it is still a spurt.
Does a growth spurt mean I do not have enough milk?: Not usually. More frequent feeding is how breastfeeding works: milk production responds to how often milk is removed, so a few days of extra feeding is what raises supply to meet a bigger baby's needs. Signs of enough milk are plenty of wet and dirty nappies and steady weight gain.
Should I give more formula during a growth spurt?: Follow your baby's hunger cues. If they finish bottles quickly and still seem hungry, offering a little more is reasonable. Paced bottle feeding helps them stop when full rather than finishing on autopilot. If you are unsure about amounts, your health visitor can advise.
Do twins have growth spurts at the same time?: Often not. Twins grow at their own pace, and one may be in the middle of a spurt while the other is feeding normally. That can make it feel like one baby is always hungry. Logging each baby's feeds separately usually makes it clear which one it is.
How do I tell a growth spurt from illness?: A growth spurt is a hungry, fussy, otherwise well baby. Illness tends to look different: feeding less rather than more, fewer wet nappies, fever, vomiting, unusual sleepiness or a cry that sounds wrong. If you see any of those, get medical advice rather than waiting it out.