My mom took me to the doctor until I was 16. As a kid I never thought much about it. She had seen me naked lots of times, in the bath and changing clothes, so it was no big deal.
When I reached adolescence, I became much more self-conscious about having her there. There was also an issue about the doctor, since he was a pediatrician, and I was growing too big for the cartoon paintings on the wall and the procedures, which required going down the hall in your underwear to be weighed and measured. At sixteen, it just wasn't cool to be standing there in briefs, with other parents and kids coming and going.
The doctor was somewhat sensitive to my situation. He would have me lay on the bench to check out my belly, pressing all around, and then shielding my privacy with his body do a quick "peek below the belt" by lifting up the waistband of my shorts and doing a quick examination of my penis and testicles. Then it was down on the floor as he seated himself on a stool and I had to lower my undershorts for the hernia check -- "Turn your head and cough." Mom had a clear view of my buns at that point, but that was all, Then the shorts came back up, and I would start to pray "No shots... no shots." If the doctor said, "You can go ahead and get dressed," I knew I was home free. If he said, "Jump back up on the bench for me," I knew I was in trouble. That meant a needle, or two or three.
The worst was if I was there for bronchitis or a sore throat. That called for penicillin, which was liberally dosed through a big needle stuck in your rear end. A shot in the arm was bad enough, but those butt shots hurt, and my mom would always get up from her chair and come over to the bench to help the doctor and the nurse hold me still for those painful injections. I hated them. But I'm sure that's where my med-fetish started, too.
Anyway, the straw that broke the camel's back when I was sixteen, having that regular physical examination, was that my mother chose the hernia part of the exam to broach a question to the doctor. My pants are down around my knees, he is handling my most private parts (no gloved in those days), and my mom pipes up behind me: "Um, Doctor, my husband and I were wondering if you had any literature to recommend on sexual development for him?" Apparently she had heard the discussions with other parents about having the "sex talk" with your kids, and wanted the doctor to help her out. I wanted to die on the spot. I was a late bloomer in the sexuality department, and the last thing I wanted was a frank discussion with my physician and my mom while he was holding my penis in one hand and digging his finger up into my groin. I decided on the spot that never again would I endure a humiliating exam with my mom in the room.
Some years ago I reminded her of that humiliating day, which she also remembered vividly. We had a good laugh about her ineptness at the "sex conversation" and all was forgiven. But I did find a new adult doctor -- that's a story for another day, the next year, and went to my next examination on my own.