A fat embolism from a BBL is an acute surgical complication, meaning it would typically happen during surgery or in the very early postoperative period, not 5 or more years later. Once the transferred fat has healed and established its blood supply, it does not suddenly enter the bloodstream years later in the way a perioperative fat embolism occurs. Years after a BBL, patients can still have other issues such as firmness, fat necrosis, oil cysts, asymmetry, or contour changes, but those are different from a fat embolism. That said, if you are asking because you currently have symptoms such as sudden shortness of breath, chest pain, fainting, rapid heartbeat, coughing blood, confusion, or severe leg swelling/pain, you should seek emergency care immediately. Those symptoms need urgent evaluation for serious causes such as a blood clot in the lungs or other medical problems, regardless of your BBL history. If you have a new lump, firmness, pain, or contour change in the buttock area years later, see a board-certified plastic surgeon for an exam and possibly imaging, but a new fat embolism 5 years after BBL would be extraordinarily unlikely.