I need a breast reduction and my insurance company will not pay for it. If my surgery is medically necessary can they still deny it?
You should review your health insurance plan documents closely, including the summary of benefits and the full plan description. Those documents will control what is and is not covered by your plan. If this is an employer-sponsored plan (i.e., you get it through work), you should be able to get a copy from your human resources person/department.
Some services are not covered by a plan, regardless of the medical necessity. Some services are only covered when considered medically necessary by a physician. Again, you need to review the health insurance plan to determine whether the service is covered if medically necessary.
You should have been provided with a denial letter from the insurance company, stating why pre-approval was denied. In that letter, it will tell you why they feel it is not a covered service, and it will also outline for you your appeal rights under the policy. If you feel that the denial is improper, then you must file an appeal according to the appeals process in your plan documents and/or contained in the denial letter your receive. If you fail to follow the full appeal process, you may not be entitled to relief even if you are correct. Most health insurance plans provide a time limit to appeal a denial, so you must make sure you have filed your appeal within the time limits.
Best of luck.