I am 18 years old and I want breast reduction but not sure if my doctor would approve?

It is difficult to tell in your case without photos or a description of your physical symptoms.   Insurance approval depends on multiple factors.  These include the patient's breast size compared to their height and weight, the plastic surgeons estimate in terms of breast tissue weight to be removed, the extent of the patient's symptoms and physical limitations as they relate to her breasts and whether the patient has sought conservative treatment for their symptoms such a s chiropractic care or physical therapy.  Unfortunately every insurance companies requirements are different.  I recommend consultation with a board certified plastic surgeon who can better evaluate your situation and write a letter of preauthorization to your insurance company. 

Hard to say without pictures. Many young women do have breast reduction at age 18 and are very pleased. You should seek a consultation with a board certified plastic surgeon who will be able to tell you if you are a good candidate and will also explain the incisions and resulting scars. Some insurance companies do cover breast reduction but have certain criteria you need to meet to qualify. When you see a plastic surgeon, you will find out if you are a candidate and the surgeon can help you apply for per-authorization. Good luck!