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What About The Wonder Weeks? When to Start Sleep Training?

Did you have another long night with multiple wakeups? And did you wake up this morning determined to change things and start teaching your child independent sleep skills?

Then your coffee starts to kick in and it’s easy to start making excuses. Maybe things aren’t so bad, you knew that having a baby would mean less sleep. Or maybe your child is just about to go through a big developmental milestone so it would be a difficult time to start.

I’ve heard many excuses about why to hold off on sleep training and making sleep a priority in the home. Developmental milestones or the Wonder Weeks concept is one of them.

The Wonder Weeks

sleep training during a developmental milestones

For those of you who aren’t familiar with it, The Wonder Weeks was developed by the husband-and-wife team of Frans Plloji, a behavioral scientist, and Hetty van de Rijt, an educational psychologist based on a perceived behavioral rhythm or leaps in developmental stages.

According to this concept, the leaps of development take place at very specific points in a baby’s life, starting at five weeks and continuing through the 20-month mark, and are accompanied by this cyclic behavior:

  • Phase 1: Sunny Weeks – your baby is happy and agreeable
  • Phase 2: Stormy Weeks – your baby is fussy due to the developmental or neurological development
  • Phase 3: Wonder Week – the new skill is mastered and the child goes back to being happy.
  • Repeat

Many parents swear by this concept and the book and companion APP are very popular. Others will tell you that the science behind this concept is flawed.

Wonder Weeks – A Flawed Concept

What makes this concept scientifically flawed? Basically, it is making predictions based on averages. Most children go through development at certain points, so you can predict that yours will too. Which is inherently flawed already, all children develop differently.

The 1992 study that this concept was founded on used a sample size of 15. It wasn’t based on direct observations, but on questionnaires filled out by mothers. Dr. Plooij’s counterargument for the small sample size, stating that if you find behavior in two individuals, “then you already have proof that the phenomenon exists and is not due to luck or chance,” doesn’t do much to shore up his credibility.

In fact, the study couldn’t be repeated.

There continues to be controversy and debate over the findings of the Wonder Weeks concept. I am not saying that your child won’t be a bit cranky during developmental stages, it happens. However, it isn’t as scripted as this study seems to predict.

If it helps you through a prolonged period of crying to think, “This is just her developing as she’s supposed to,” then high fives all around. You need all the support you can get, and I say take your mental health boosts where you can find them.

When Should I Focus on Sleep?

The reason that I bring up the Wonder Weeks concept is that often parents think that they should wait for their child to reach a specific milestone before putting a priority on sleep.

I hear, “Should I wait until my child is done teething?” or “What if I get started too early or too late?”

My answer is that outside of a diagnosable health issue, there is absolutely no “wrong time” to teach your baby to sleep well.  Right before a “sunny week,” right at the tail end of a “stormy week,” or smack dab in the middle of a “wonder week,” are all perfect times to get the ball rolling. There’s no developmental milestone, no specific week, and no time in a baby’s life that could be considered the wrong time to get them sleeping well.

Adequate sleep is essential to the health and well-being of everyone in your family. I don’t know any pediatrician that would disagree.

When Should I Start Sleep Training?

We recommend waiting until your child is four months old to start sleep training. However, we do have tips to promote strong sleep skills for those with children younger than four months. Schedule a chat with us if you’d like to know more.

Just a heads up, for those starting sleep training, the first few nights can be a bit rough as everyone becomes adjusted to the new schedule, so we suggest waiting if you’re headed on holiday soon or you have an early workday. However, don’t delay your plans to help your baby develop their sleep skills due to some upcoming milestones.

And guess what? Your child is going to go through new milestones week after week and your child will transition easier and happier through them if they’re getting the sleep they need.

Get Started on Your Sleep Journey with Our Team

If you’re ready to help your child sleep through the night but you just don’t know where to start, I have a free e-guide – Five Steps To Getting Your Child To Sleep Through The Night. Or if you’re ready to have someone help you through this process, let’s chat.

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