Hi,
Any reason why my three year old dog could be wetting her bed only after her morning walk?  She's been spayed but when we asked the vet about this he found it strange too and thought she was a bit young to be affected by incontinency due to the spaying.  Anyhow, it isn't consistent and doesn't happen every day, and never through the night, anybody have any ideas on this?
Thanks in anticipation.

Maybe she feels the need to affirm HER place after being outside where there is so much competition?

Has she had any traumatic happening on her morning walk that could have started this 'ritual' off?

I'd suggest you alter the pattern of how you do things for a few days and see how this effects thing - instead of letting her go to her bed after the walk take her to another area for training or play to distract her for a while.