During the last decade liposuction has become the most common aesthetic procedure. It has also become the most common aesthetic procedure performed by physicians not trained in plastic surgery. New developments such as the tumescent technique, finer cannulas, and, finally, the technique of ultrasound-assisted lipoplasty (UAL) have been paralleled by reports of larger amounts of extracted fat. At the same time we see an increasing number of fatal complications. I have undertaken an investigation of 28 patients during 16 months, undergoing liposuction with UAL, to find out how the procedure affected them in terms of blood loss. I found that, while undergoing UAL, our patients lost up to 53% of their blood volume on postoperative day 1, and the average patient still had a loss of 20% of the blood volume 1 week postoperatively.