Does Hair Transplant cause existing hair to fall out?

[whatthehair]

As title says. I had a hair transplant 9 months ago with a reputable surgeon highly rated on this website. Around 1500-1600 to the frontal area. Had thinning on the right side of head, which inspired the hair transplant. 

Currently the right side looks great. But the left side it's as if my existing hair was replaced by my transplant hair. Also seeing some thinning of my frontal hair line. Keep in mind, my density in the left and frontal area have always been great (and it was reinforced). 

Does hair transplantation "replace" existing hair? Or does existing hair take longer to grow? 

[Rafael Manelli]

There are two main possibilities 

1. You’ve had permanent shock loss

2. Your hair loss has progressed naturally 

Do you have photos?

[gillenator]

It sounds like you have a diffused thinning pattern and yes some post-op shock loss…and yes a procedure in a diffused area can advance the loss of the existing native hair…I would also like to see some pics.