How dangerous is liposuction and fat transfer to the hips?

queenpeaches  At 19 years old, your first option is diet and exercise, not liposuction. If that fails, liposuction with fat transfer to the hips is a reasonably safe procedure when performed by a board-certified plastic surgeon. Fat transfer to the hips does not carry as many serious complications as fat transfer to the buttocks. Be certain to consult with a board-certified plastic surgeon to explore all options. Good luck.

Fat embolus is a very serious and known complication of fat transfer (which has been recently spotlighted in the media). While it is true, injection of donor fat into the infra-muscular plane (within the muscle) increases fat viability, this does come with a significant increase in risk. There are large vessels deep to and within the muscle which can be inadvertently injected while grafting leading to a fat embolus. The consequences of such a complication are very serious and life threatening.
At American Society of Plastic Surgeons Hot Topics (2016), data from AAAASF (ambulatory surgical certifying body) was presented, suggesting that BBL/gluteal lipoaugmentation demonstrates a dramatically higher risk profile than other surgeries. The Aesthetic Surgery and Educational and Research Fund has convened a task force as well. The hope is that we will have more concrete guidelines for addressing these very serious complications.
That being said, the safest way to avoid fat emboli is to stay in the subcutaneous plane (at the expense of fat viability) and avoid the deeper muscular plane. If grafting of the deep plane is planned, surgeons should consider blunt cannulas and aspiration prior to injection. Using a supra-gluteal approach to minimize the risk of inadvertent intravascular injection has also been proposed. While this will likely impact graft viability negatively, it will also lower the risk of a serious complication.
According to AAASF data the risk of death from BBL will range from 1:3000-1:6000 (subcutaneous grafting should reduce this risk relative to intramuscular grafting). By comparison the risk of fatal complication from abdominoplasty is 1:13,000. It is unclear how the relative risk falls with subcutaneous injection vs. intramuscular injection (however, in all likelihood, it is less).
No result is worth risking one's life for. I find that the patients who focus not on the volumization but rather the contouring benefits of the liposuction are happier than those whose sole goal is size. Relatively speaking, the subcutaneous plane is the "safe" plane.
In summary, the procedure can be safely performed, however, they should be performed by a board certified (ABPS) plastic surgeon with experience. These risks should be discussed as well as the strategies being employed to avoid them.