We're still using ours, although Jenna is only 5 months old, but it is something I have wondered about too. I was thinking that maybe if she starts rolling off it all the time we'd stop using it then. I guess there comes a time when you just have to stop - otherwise it'll still be on when they're 10 years old!! I just don't know when to stop. I think we might keep using it until she is out of the cot and in a bed, so sometime around 2 I think?