I have a pretty odd question! I tried to research it but couldn't really find anything.

My twin sister and I got a birth control implant about two years ago but had it taken out last year. The doctor noted that it was interesting because she had a scar tissue build up (which she said is pretty normal) whereas I did not have any scar tissue at all, (and she said that was pretty uncommon). They were inserted by the same person so I imagine the techniques were similar. We both received numbing shots and didn't flinch. So could anyone tell me why I didn't build up scar tissue but she did? It's completely a random curiosity!

I will add too that I have a VP shunt I've had for 18 years and I was wondering if that would have any kind of effect on the way my body reacts to implants since my body got used to something foreign early on. Thanks!