The Science of Why Babies Cry More and What Parents Need to Know

You may have noticed that your baby sometimes seems calm and relaxed…and then goes through a ‘fussy’ phase, where they seem to cry no matter what you do. Do these fussy phases happen on a predictable schedule? Is it predictable for all babies…and for all parents? In this episode, we dive into the research behind the theory of the Wonder Weeks, as described in the books and app. This popular concept suggests that all babies experience predictable periods of fussiness in preparation for going through developmental ‘leaps,’ but the science behind it may be much more limited than you expect. We break down the available research, explain why babies might cry more at certain stages, and help parents understand the truth about these so-called Wonder Weeks.

What topics do we cover?

How Wonder Weeks became a popular theory
What actual research says about baby crying phases
Ways to support your baby during fussy times, whether or not Wonder Weeks apply

By the end, you’ll feel more informed about why babies cry and have a clearer idea of whether Wonder Weeks is a useful tool for understanding your baby’s needs. Episodes Mentioned:

Books mentioned in this episode:

The Wonder Weeks by Dr. Frans Plooij and Hetty van de Rijt

Jump to Highlights: 00:03 Introduction to the Podcast and Wonder Weeks 02:19 Background on the Plooys and Their Research 05:43 Methodology and Findings of the Plooys' Study 10:20 Criticisms and Limitations of the Plooys' Study 20:11 Replication Studies and Their Findings 59:42 Conclusions and Implications References: Aldridge, J. Wayne, et al. "Neuronal coding of serial order: syntax of grooming in the neostriatum." Psychological Science 4.6 (1993): 391-395.

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230: Do all babies have Wonder Weeks? Here’s what the research says

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230: Do all babies have Wonder Weeks? Here’s what the research says