An anus stretches the same regardless of gender. Same goes for boys and girls: you have to do it very consistently to get to the point where the hole doesn't contract back to it's original size. The thing doctors are more likely to notice than a size issue is any scarring or tears. This is very common with anal sex because most people don't take it slow enough and do the prep work beforehand of using fingers/toys etc to stretch your hole and get it used to slightly bigger and bigger sizes until it's ready to take a penis. It's very dangerous to do anal without this prepwork because there is only one protective layer in your anus and if you make even the slightest tear, you're open to getting all sorts of diseases or infection, etc. Whereas a vagina has about 30 layers of interior protection to get through before there is an 'open wound'. That's why Aids affected gay men way more than women originally, and still does tend to.
So, yeah, if you do it right, then your doctor shouldn't be able to tell.
Hope this helps.
Depends if you are the giver or taker. If you are the taker, after enough times it stretches. But if you are the giver, no one can tell unless you tell them.
on a man, i very much doubt it, on a woman probably yes because of the way it streches the anal hole.
even with guys taking it? it streches?
so would it do the same thing?