生後2〜3週の急成長期：サイン、授乳の作戦、睡眠のヒント | Nurtura Daily

When does the 2 to 3 week growth spurt happen?

The AAP says growth spurts typically happen around 7 to 10 days and again between 3 and 6 weeks, and many guides mention 2 to 3 weeks. A few days early or late is normal.

What are reliable signs at two to three weeks?

An appetite jump, evening cluster feeding, shorter naps, extra night wakes, clinginess, and steady or higher wet diaper counts.

How long does it last?

Usually a few days (NHS). If it drags on well beyond that without an appetite jump, look at room temperature, visitors and travel, and talk to your pediatrician.

Do we change our routine?

Keep it simple: feed on demand, start wind-down a little earlier, keep evenings calm and keep safe sleep basics. Avoid starting new sleep-training methods now.

Tips for breastfeeding vs formula?

Breastfeeding: feed as often as your baby wants, offer both sides, and get latch help early if it hurts. Formula: responsive bottle feeding with pauses, and follow fullness cues so you do not overfeed.

When should we call a doctor instead of assuming a spurt?

A temperature of 38°C (100.4°F) or higher under 3 months, not interested in feeding, fewer wet diapers, or signs of dehydration need urgent medical advice. Breathing difficulty, blue or gray skin, or a baby who is hard to wake: call your local emergency number.