I was just wondering what would be the requirements for my 16 year old daughter to get a boob reduction and through insurance she has really bad back pain. does it have to be done by someone in the united states? and how small can she go?

Start with an evaluation by her pediatrician, who will be able to coordinate locally based on findings.

Agree with Dr. P. Insurance usually covers medically indicated breast reduction surgery. It will be important for her to have counseling before the surgery so that she make a healthy adjustment to her new body image. Get her HPV vaccine. Wish you and your daughter good health!