When do babies stop flailing their arms when dropping off to sleep!?

[ladypop]

...I only ask as our 15 wk DS has been swaddled every night as it really suited him to help settle as well as stopped him knocking his dummy out every 10 seconds whilst he tries to drop off to sleep.
Now he is like Houdini and seems to wriggle his arms free during the night at some point. Not to big a deal but tonight I couldn't even swaddle him as he was too strong and wriggly to let me! I give up, I thought, time for the Gro bag!
His dummy usually falls out when he is in a deep sleep, but during the early hours I have to put it back in about every hour as he wakes quite frequently any time after 4am....just worried his loose arms will make this occurance even worse!

my 4.5 year old still does it.

I swaddled DD until she was 6 months, I used a cotton fitted cot sheet and wrapped her really tight. I stopped swaddling her when this hot weather started and it took her about 2 weeks to get used to not being swaddled and not needing her dummy put back in every hour. Hopefully if you keep going with just the grobag things will improve. I now put long sleeves on DD as her arms are uncovered and that also seems to have helped, not sure if some of her wakings were because she was cold?

tacal beat me to it on age, but my 10 mo still does it..