I've never had an actual couples exam where my spouse and I were each examined by a doctor in the same room at the same time. However, I have had three experiences that touch on the subject of this thread.
The first was when my wife was pregnant, I was in the room for her first exam. She was due for her annual so the doctor examined her with me sitting there. I was sitting above her head and off to the side, so I didn't get to actually see anything, but that didn't stop me from getting all kinds of turned on!!!
The second experience was when my wife and I went to the "consultation" with the urologist before my vasectomy. We both thought that just meant talking about the procedure and scheduling a date for it. We both were surprised when at the end he said drop your pants and have a seat on the table. Only this time, my wife had an excellent seat for the exam. While laying back on the table, I could look down and see the doctor handling my junk, my jeans and underwear bunched up at my knees, my feet sticking straight up in the air, and finally my wife sitting at the business end of the table smirking at me. Classic!
The third doesn't involve my spouse, but a doctor and two nurses in the exam room. It was my first time to this dermatologist and my first time for a "total body skin exam" as an adult, so needless to say I was extremely nervous. I had read so many varying stories as to what to expect during one of these exams (standing, laying down, sitting, completely naked, underwear, gown, no gown, ...) my trepidation and anxiety were dialed to 11. So after the nurse tells me to take everything off and put on the gown, she then casually mentions that they recently started using EMR (Electronic Medical Records) and she is still getting trained on it, so there will be another nurse that will accompany her and the doctor for the exam. So after the light knock on the door, in walks the doctor, the first nurse, and the young, skinny, pretty, 20 something year old nurse. Oh great, that's all I need! ...It was a very humbling experience.