Our 18 month old daughter's labs are done at the Mayo clinic. Her blood is taken at the hospital in northwest Michigan (Traverse City) and then sent to Mayo. We usually get her results back in about 3-5 days. The only propblem we have is the communication between the lab her regular doctor and her ped. endo. at UofM. Sometimes the results are at one place and not at the place of most importance and that tends to slow the time for us to here if we have to change meds or not. I would suggest being quite agressive on getting the results back. God bless.