Reducing the stomach is an operation that is performed on people suffering from morbid obesity. Currently, there are operations that do not require traditional open surgery, but can be performed through endoscopy. The reduction of the stomach by endoscopy, also known as POSE surgery, consists of a new technique performed orally and without the need for incisions. This minimally invasive procedure begins by inserting an endoscope through the mouth to reach the stomach, where folds are made to reduce its size and capacity, and to make its emptying slower. The benefits of stomach reduction without surgery are that it offers permanent results without external scarring, without hospital admissions and it is a safer procedure.