I've had a lot of medical procedures and exams, and all but one time (when conscious, of course) I've been asked to remove my underwear if that sort of thing was needed, and offered some sort of gown or sheet.
One time I was having some sort of abdominal pain at the top of my pelvis, and my gastroenterologist decided it was probably urinary, so he sent me to a urologist.
We were talking in the room, which was a bit dimly lit (which already had me a bit uneasy) and he asked me to stand up and remove my shirt and trousers.
I did so, although I really had expected to be in a gown. There I was in my underwear (which were already disposable due to other problems, which I had not explained so I was feeling embarrassed) and he suddenly pulled my underwear down to my knees, pulling them inside-out as he went.
I stood there on the verge of shaking as he fiddled with my genitals...I was not ready for it, he had not even put gloves on so I did not expect anything. I'm sure it was a normal sort of exam, but I was sort-of starting to zone out.
He had me lift one leg and then the other, and as I did so my underwear fell down to my ankles.
Then he went over to wash his hands. I did not know what I was supposed to do; I was afraid to do anything. So I stood there for at least a minute with my underwear inside-out around my ankles. He finally turned back and, almost as an afterthought, told me to get dressed.
I put up with him for one more visit (on which he did nothing to me), then vowed to never return. Which I have not.