I have always been 24/7 - and yes have had that test, and LOTS of others.
No issue at all to worry about there, it's just another pair of underwear as far as they are concerned.
It's VARY rare to have any issues at all there in any medical setting!
I did have an issue with a hospital when I had to stay there for a few days a few years ago (I WILL NOT use that hospital for anything ever again!) and that was mainly the one nurses aid just plain did not want to deal with it.
The ONLY other time I can remember of anything at all in a medical setting was not actually an issue, just a little strange - not in itself, more the fact this was from someone I had never seen before at all. That was following some procedure (don't recall what one now, but something you had to be out for) - and all that actually was - when I was just waking back up, but for sure could still feel the anesthesia, right in front of me, that nurse tells my wife "Put on his Pamper.".
Other than those two incidents - the only times it was bought up at all in a medical setting was by someone I had already dealt with a lot (Like an ER nurse, staff in the hospital I do use ex.) and that use mostly honestly just seeking information - and I KNOW those people would not have said anything if it weren't for the fact that, while only on a professional level, we did know each other - well enough to recognize each other on site, even if it was like in a store or something like that. And mostly having to do with the quality and easy of use (on them) of the diapers I had, compared to what they "get stuck" using if someone that is IC ends up there, and does not have their own with them.
SO just those two times at all, and that is out of a life-time (Just over 50 years) - therefore I would have to say it's a VERY good bet to say it's not likely anyone in a medical setting is going to say anything, or care - and if they do say anything at all (HIGHLY UNLIKELY) that is likely to maybe seem a LITTLE strange, but really nbd.