Plastic surgery can be done for a number of reasons, with most falling into two camps. One is the cosmetic side of surgery, where you are having the surgery only for cosmetic reasons. The other is the medically necessary reconstructive side, in which your surgery is done because the reconstruction is necessary for you to have a vital body function. Insurance companies are often loath to pay that much for plastic surgery because it's often done just for cosmetic reasons. So, if you want to have medically necessary surgery, it's important that you do what you can to show that it is not being done just for looks.
Your past history regarding the problem is one way to show the insurance company that you needed the surgery. For example, if you are a woman and have had repeated problems with a bosom that is too heavy, thus causing massive pain in your back and making it impossible to do much without pain, those records of unsuccessful back treatments can go a long way toward getting breast reduction surgery paid for. On the other hand, if you've never seen a back doctor for back pain and are just a bit tired of having a large bosom, the insurance company is going to consider your surgery to be cosmetic.
Even if there is little patient history, you could still have a chance. For example, if your newborn has a cleft lip and palate, surgery is necessary to repair those so the child does not have delayed speech when he or she gets older. There are additional physical effects from having a severe cleft palate. The surgery may seem cosmetic because a lot of it involves facial work, but it's accepted that a cleft lip and palate can affect speech development. In that case, the surgery should be considered medically necessary.
Getting specialist recommendations for the surgery is also crucial. If you want a breast reduction because of back pain, getting recommendations for surgery from a back specialist may be necessary. If you're getting older and your eyelids are drooping so much that they are blocking your sight, a recommendation for blepharoplasty from an ophthalmologist may be necessary. The more professional advice you can get that shows that the surgery is a medical issue, and not a cosmetic issue, the better off you'll be.
It's never a guarantee what the insurance company will do. A procedure that you and your doctor consider medically necessary, such as excess skin removal after weight loss, may or may not be covered even if the skin is causing problems. But don't give up. Speak with a plastic surgeon, like Barry, Ronald C, about how they work with insurance companies to show that the surgery was necessary and should be covered by insurance. You may be pleasantly surprised at what the surgeons' office staffs can do.