You should first ask yourself what message you're sending your kids about nakedness. It doesn't have to be viewed as something dirty or obscene. But, of course, for the sake of propriety, you have to stop once they reach a certain age. My cousin, who has a son, told me that at age 5 or 6, my nephew would already cover his eyes whenever he'd see his mom dressing up or even, right after she'd step out of the shower. Came across this article which might help enlighten you: https://ph.theasianparent.com/when-should-you-stop/ Hope it helps!
hmm, it really depends on how comfortable you are and how comfortable your kids are with seeing you naked. haha. usually kids start finding it weird at around 7 or 8. though, you shouldn't make a big deal about it. :)