Newborn Growth Spurts: When They Happen (3 Weeks, 6 Weeks, 3 Months) and What the Evidence Says

When do newborns have growth spurts? Pregnancy, Birth and Baby places newborn growth spurts at about 2 to 3 weeks, 6 weeks and 3 months. For a few days your baby wants to feed more often and is fussier, then settles back. Research has not confirmed fixed ages, so treat these ages as common times a surge may come.

The worry that comes with a surge is usually about milk. A baby who fed every three hours last week and now wants the breast every hour can feel like proof your supply has dropped.

Pregnancy, Birth and Baby says cluster feeding is not usually linked to low supply. The Australian Breastfeeding Association (ABA) says frequent feeding doesn't necessarily mean a baby isn't getting enough.

The last section covers when to call your nurse, GP or the ABA helpline.

When do newborns have growth spurts?

Newborn growth spurts are most often placed at 2 to 3 weeks, 6 weeks and 3 months, and some sources add about 10 days and 6 months. Each is a few days of more frequent feeding and fussiness. The ages are rough guides. A surge can come a week early, a week late, or at an age no list mentions.

• About 10 days: Several days of more frequent feeds (La Leche League Canada, supporting evidence).
• 2 to 3 weeks: Cluster feeding during a growth spurt (Pregnancy, Birth and Baby; La Leche League Canada).
• 6 weeks: Fussier, wants to eat more than usual (Pregnancy, Birth and Baby; La Leche League Canada).
• 3 months: Fussier, wants to eat more than usual (Pregnancy, Birth and Baby; La Leche League Canada).
• 6 months: More frequent feeds for a few days (La Leche League Canada).

Pregnancy, Birth and Baby names three ages. Its cluster feeding page(opens in a new window) says babies may cluster feed during a growth spurt at around 2 to 3 weeks, 6 weeks and 3 months. La Leche League Canada(opens in a new window), a breastfeeding support charity, adds about 10 days and 6 months, and says a surge "may happen at any time".

The 3 week growth spurt

The 3 week growth spurt is the first age on the Australian list. Pregnancy, Birth and Baby places it at 2 to 3 weeks, often as a run of cluster feeds. The ABA says young babies feed 8 to 14 times or more in 24 hours, so a jump towards the top of that range is not a warning sign on its own.

The 6 week growth spurt

The 2 month page(opens in a new window) at Pregnancy, Birth and Baby says babies often have a growth spurt at about 6 weeks. It "might make them fussier because they want to eat more than usual". Two other things around 6 weeks can make it harder to read:

• Crying often peaks around 6 to 8 weeks, says Raising Children Network(opens in a new window). Our 2 month milestones guide covers the crying peak.
• Breasts may feel softer around 6 weeks. Raising Children Network(opens in a new window) calls this a normal change and says your breasts are still making enough milk.

Softer breasts and a hungrier baby in the same week can look like a supply drop. On its own, it isn't one.

The 3 month growth spurt

The 3 month page(opens in a new window) says babies may have a growth spurt at about 3 months and want to eat more than usual. Around the same age, the ABA(opens in a new window) notes that weight gain in breastfed babies usually slows from 3 to 4 months. It says there's probably no need to worry if a 4 month old is no longer gaining as quickly as before.

Growth spurt signs and how long they last

The signs of a growth spurt are a baby who suddenly wants to feed more often, is fussier or clingier, and may sleep less, for a few days in a row. Most settle within 2 to 3 days, says La Leche League Canada. The ABA says fussy periods can sometimes last a few days or even weeks.

Signs parents describe, drawn from the ABA(opens in a new window) and Pregnancy, Birth and Baby:

• Feeds come closer together, sometimes every hour, day and night.
• Your baby comes on and off the breast or fusses at it.
• More unsettled between feeds, and clingier than usual.
• Shorter sleeps, or more night waking.
• Wet nappies stay the same: heavy, with pale wee.

Nappies are what separate a surge from a problem, and so is how long it lasts. La Leche League Canada says a baby usually returns to their previous feeding routine after about 48 to 72 hours of frequent feeds.

Growth spurt, cluster feeding or a supply problem?

A growth spurt is a few days of extra feeds, cluster feeding is a run of short feeds bunched into a few hours, and a supply problem shows up in nappies and weight. Pregnancy, Birth and Baby treats a growth spurt as one reason babies cluster feed, so the first two overlap. Nappies and weight are what tell all three apart.

A possible supply problem looks different:

• When: Any age, and it doesn't pass.
• How long: Carries on past a few days.
• Wet nappies: Fewer than 5 heavy, or dark wee.
• Poos under 6 weeks: Few or none.
• Weight: Not gaining after the first week.
• What helps: See your nurse, GP or ABA counsellor.

The nappy and weight checks come from Raising Children Network(opens in a new window) and the ABA(opens in a new window). A baby getting enough milk has at least 5 very wet disposables or 6 wet cloth nappies in 24 hours after the first few days, soft poos 3 to 4 times a day under 6 to 8 weeks, and gains weight.

Our guide to cluster feeding and the witching hour covers the evening pattern in detail. For the wet nappy count by age, see how many wet nappies a day.

Does a growth spurt mean my supply is low?

No. Pregnancy, Birth and Baby says cluster feeding is not usually linked to low supply, and the ABA lists frequent feeds and cluster feeding as normal. The ABA's page Is it really low supply?(opens in a new window) adds fussing at the breast and softer breasts to that list. Milk supply follows demand, so extra feeds tell your body to make more.

Read weight over several weeks. The ABA(opens in a new window) says gains vary from week to week and a month's average is often more helpful.

What the evidence does and doesn't show

Feeding surges are real and common, but research has not found growth spurts at fixed ages in the first year. Health services, pregnancy and breastfeeding websites and some public health advice repeat the same ages, but a 2024 review found no study that ties infant growth to those ages. The advice for parents stays the same.

Three sources, read together:

• Pregnancy, Birth and Baby names 2 to 3 weeks, 6 weeks and 3 months, and describes the extra feeding as a growth spurt.
• The Australian Breastfeeding Association has moved away from the growth-spurt explanation. It says fussy periods were once thought to be caused by growth spurts or appetite increases. It now links them to changes in the developing brain and to temperament.
• A 2024 review in the journal Nutrients (supporting evidence) searched the research for infant growth spurts and found six relevant studies.

Australian Breastfeeding Association · Fussy periods

Research shows that the amount of breastmilk a baby takes remains about the same from 1 to 6 months of age.

The 2024 review(opens in a new window) by Davanzo and Baldassarre found that babies measured very often do grow in bursts and pauses. Neither of the main studies found those bursts arriving at regular times or at a set age. The authors add that the WHO growth charts show no speed-up in growth at these ages.

The review's main concern is what the label does. Crying, fussing and short gaps between feeds are often read as low supply, and "growth spurt" is often the explanation offered.

The review cites the Lancet Breastfeeding Series, which names a mother's sense that she has too little milk as a major reason for starting formula and stopping breastfeeding early. The authors call growth spurts "a simple compelling theory".

Whatever drives the extra feeds, the answer is the same: feed on cue, and let nappies and weight tell you whether your baby is getting enough.

What this means at home: a few days of hungry, unsettled feeding is common in the early months. You respond the same way whether or not it falls on a named week.

What helps during a feeding surge

Feed whenever your baby shows hunger cues, and set yourself up to rest. The ABA's advice on increasing supply(opens in a new window) is to follow your baby's cues, and it says fussy periods when a baby wants to feed more usually settle in a few days. The more milk your baby removes, the more milk you make.

Practical things the ABA, Raising Children Network and Pregnancy, Birth and Baby suggest:

• Feed on cue. Some feeds will be close together. Short feeds count too. Our newborn feeding schedule guide covers how often babies usually feed.
• Offer the second breast, and the first again if your baby is still keen.
• Try a top-up breastfeed if your baby doesn't settle. Raising Children Network says you'll have more milk again in 20 to 30 minutes, even after a big feed.
• Comfort in other ways too. A warm bath, a carrier, dim lights and less noise can help an unsettled baby.
• Look after yourself. Keep water and snacks within reach, and rest when your baby sleeps.
• Hand over everything else. A partner or family member can take meals, washing and settling between feeds.

If you are thinking about a formula top-up because of a surge, talk to your child health nurse, a lactation consultant or the ABA helpline first. The ABA notes that formula can make a baby less hungry for breastmilk, which can lower supply.

If your baby is formula fed or mixed fed

Formula-fed and mixed-fed babies have hungry stretches too. The Sydney Children's Hospitals Network(opens in a new window) describes cluster feeding as normal, especially during rapid growth, whether a baby has breastmilk, formula or both. Its advice is to feed to your baby's hunger cues and follow your nurse's or doctor's guidance. Our formula feeding guide covers amounts by age.

When to call your nurse, GP or the ABA helpline

A feeding surge that settles in a few days, with good nappies, is normal and needs nothing more than feeding on cue. Call for advice when it doesn't settle, or when nappies, weight or your baby's behaviour change. You can phone the ABA's National Breastfeeding Helpline(opens in a new window) on 1800 686 268, 24 hours a day. Pregnancy, Birth and Baby's maternal child health nurses are on 1800 882 436.

You know your baby's normal. If a surge feels different from the ones before, or something about your baby worries you, call.

Seeing a surge in your feed log

On broken sleep, three days of hourly feeds blur into one. A tally of feeds per day, on paper by the bed or on your phone, shows whether today is really different from last week and when it eases.

BabyLog's free Summary charts feeds per day across the last 14 days, with a 7-day average line. A surge shows as a few taller bars that drop back to your baby's usual, and feeds your partner logs land on the same chart. BabyLog doesn't label growth spurts: it shows the count, so you and your nurse can read the pattern together.

If a daily count would help in the next surge, you can start free in your phone's browser.

Common questions