In every one of the half dozen or so hunter safety classes I've attended we were advised to NEVER, EVER climb a fence, a tree, a ladder or a ditch, stream or any steep embankment with a LOADED firearm!
If I found someone in my hunting party climbing into his stand with a loaded gun, that would be last time I would ever hunt with them again. He or she puts not only himself in extreme danger but others in the party as well.
It is one the fundamentals in firearms safety and fundamental COMMON SENSE!