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🍼 Feeding · From 3 days to 9 months

📈 Growth spurts: the 3-6-9 rule

All of a sudden, your little one wants feeding round the clock, screams the second you put them down, and only sleeps in fits and starts. Don't panic, mate: it's not colic, and it's not 'dodgy milk': it's a growth spurt. They hit at fairly predictable moments according to the 3-6-9 rule, and usually last between 24 and 72 hours.

When to expect it

  • 3 days (often the exact moment you get home from the maternity ward, just to keep you on your toes).
  • 3 weeks.
  • 6 weeks (often the toughest one for crying and nonstop demands).
  • 9 weeks.
  • 3 months, 6 months, and 9 months.
  • The tell-tale signs: rapid-fire feeds, a grumpy baby whenever you dare set them down, and broken sleep for 1 to 3 days.

The survival protocol

  1. 1. Breastfeeding: let them feed on demand

    They'll be cluster feeding back-to-back. All that sucking is nature's way of telling mum's body to ramp up milk production. Avoid reaching for top-up bottles of formula without medical advice: it'll throw off the supply-and-demand signal.

  2. 2. Bottle-feeding: bump up the volume

    If they're draining every single bottle and still rooting for more, add an extra 15 to 30 ml per feed.

  3. 3. Your role: 100% pure logistics

    Sort the meals, keep the place tidy, bring mum a giant bottle of water, and handle the soothing between feeds. Your primary mission is giving her a chance to breathe between shifts.

  4. 4. The dad hack

    A growth spurt is a 48-hour sprint, not your permanent new normal. Don't tear up your whole routine or lose your head: baby is just placing a bulk order for a growth surge.

Classic mistakes

  • ❌ Thinking the milk isn't enough anymore Demand increases specifically to kick-start milk supply. Giving up on breastfeeding right in the middle of a spurt is almost always a false alarm.
  • ❌ Ignoring genuine red flags A fever, flat-out refusing feeds, fewer wet nappies, or unusually weak, high-pitched crying are not growth spurts. Call your GP, health visitor, or your local emergency number. This guide is no substitute for medical advice.

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This guide doesn't replace medical advice. When in doubt, call your doctor or your local emergency number.