When to switch from a swaddle to a sleep sack?

So your baby is in a swaddle and sleeping really well. And you start to wonder - when do babies stop wearing swaddles? And will the transition out of the swaddle just ruin my little's wonderful sleep habits?

OR maybe your little is more like my 2nd kid - and despite the proven benefits of swaddling - it just isn't your kid's thing. They bust out of it every night. Their sleep is not improved once once by being in it, and you're READY for anything to fix the night time sleep issues. 

Either way - it's relevant to know when you should move out of the swaddle to the sleep sack. 

According to the American Academy of Pediatrics, you should stop swaddling your baby at the first signs of rolling. When will this happen? Typically it starts around 3-4 months of age, though there are rare occasions it happens before, usually these are just anomalies. (Both my kids rolled once or twice around 4 weeks, but neither truly figured it out until 1-3 months later.) 

The risk of having your little in the swaddle when they start to roll is that they might roll onto their tummy and with their arms pinned, have no way to move themselves out of the position. 

There is another camp, driven by Dr. Rachel Moon (who happens to be the lead author on the AAP safe sleep recommendations) that parents should stop swaddling their babies by 8 weeks. While this is not the formal recommendation of the AAP, Dr. Moon cites cases of children suffocating from rolling while swaddled at 2-2.5 months old as her reasoning for the recommendation.

What if your little doesn't love the swaddle - do you have to use it? 

A sleep sack is totally safe to use from birth. So if you've given the swaddle a shot for 3 solid days, and it's still not making a difference, go ahead and move to a sleep sack.

Just make sure it is appropriately sized, and cannot pull up over their faces.

For my kids - my daughter was swaddled until we sleep trained her at 15 weeks (she was definitely not rolling at that point.) For my son, we swapped to a sleep sack at 4 weeks because the little Hulk was busting and squirming out of every swaddle contraption we had. Once we dropped it - his sleep improved (this is definitely rare, but worked well for us!)