Yup. I had a friend in high school whose mother was an MD. She (my friend, not her mother) would clean the offices at her Mother's practice and those of a few other doctors on the weekends. One of them was between my work and my home, when I saw her car there on my way home, I'd stop and say hi. We were chatting in the office once when a girlfriend of hers stopped by as well. We wandered around following her as she vacuumed. We passed an exam room where the exam table had the stirrups extended and the friend hopped up on the table and put her feet in the stirrups. My friend snapped at her "No! you can't do that, now I have to clean that entire table!" The friend said "Oops, sorry, but its kinda sexy to be up on here when I'm not getting examined". She cleaned the table and the friend left, then I left a few minutes later and went home and jerked off thinking about fucking her friend in the stirrups.
Some time later I saw her there again and stopped in. She was cleaning and we chatted and she went into the same room and the table had the stirrups out again. She hopped up and sat on the side of the table like she was just taking a break. "Won't you have to clean it now?" I asked. She said no, and that she actually wasn't supposed to clean anything in the exam rooms aside from vacuuming the floors. Then she swung her legs around and put them in the stirrups and commented that her friend was right, that it did make her feel kinda sexy. She may have rubbed herself through her sweat pants a bit too, I couldn't quite tell for sure. "I don't think it'd even be possible to have sex like this though, my legs are too close together and my butt is too high off the ground". I wasn't going to pass up the chance to do some hardcore flirting, so I stepped between her legs and gently put my hands on her thighs. She was right, she was too high up and I wouldn't have been able to get close enough between her legs. "Nope, too bad" I said. To that she said "pull out the shelf" she had to explain that to me, but at the base of the table there was a step-stool like shelf that pulled out. When I stood on it we were pelvis to pelvis. "uh oh" she said as she reached down beside herself and popped the release that let the back of the table rise up behind her. I was getting turned on but didn't think she was actually wanting to have sex, so I just said "nice" and stepped down off the shelf. She took her feet out of the stirrups and swung them around the side. I was going to walk away but she said, "turn the crank under the base of the table-top". I bent down to reach it and as I turned it the stirrups spread apart more. When I stood back up she had taken her sweats off, she swung her legs back around to face me and pulled me back onto the step by my belt. "Let's try." I won't bore you with the history of our relationship, but were were friends, not lovers, although we had made out a few times, one time wearing just swimsuits, but that was as far as we'd gone, although we had both lost our virginity (separately) since then. She undid my pants and I stepped back and decided to go for it. I stripped off and turned to lock the door, just in case. By the time I turned back around I was hard and she was naked. She put her feet up and I stepped on the shelf and immediately slid my hard dick into her and we went at it. It didn't take long before I was ready to cum. I knew she was on the pill so I pulled us together by her thighs and came inside her. I pulled out and kissed her, she put her fingers inside her spread pussy and wiped some of my semen out and rubbed it around her pussy and pubic hair. We got dressed, kissed again, and left. Needless to say, our relationship got weird after that, but that isn't the point of this story. To this day it is some of the hottest sex I've ever had.
Edit: I never thought about it until I wrote the story out, but I imagine that is how I developed a medical fetish.