A developmental leap is a popular term for a period when a baby is temporarily fussier, clingier, feeds more or sleeps worse, believed to coincide with a jump in development. The idea comes from the book The Wonder Weeks, which predicts 10 leaps in the first 20 months.
Key takeaways
- Babies do have fussy patches, often around new skills.
- Leap calendars come from small studies and have not been reliably replicated.
- Every baby's timing is different.
Is there scientific evidence?
The leap schedule was first described by Hetty van de Rijt and Frans Plooij from observations of a small group of babies. Independent attempts to replicate the precise timing have had mixed results, so leap calendars are best seen as a rough guide, not a timetable.
What you can do
- Watch your baby rather than the calendar.
- Offer extra comfort and keep routines steady during fussy patches.
- Rule out illness, hunger or teething before assuming it is a leap.
When to talk to your doctor
If your baby seems unwell, has a fever, feeds much less than usual or loses skills, see your doctor instead of putting it down to a leap.
