Hi and thanks for the query, management f ovarian cyst, either through simple observation, medical or surgical treatment takes many parameters into consideration. this depends on the type of cyst, whether organic or physiologic, the size of the cyst and the clinical condition of the patient. The past medical history and obstetric history is also considered. A cyst of this size, 9cm, is actually very large and is exposing you to certain complications. These complications are mainly torsion, infection and rupture. rather than wait and intervene maybe, as an emergency surgical intervention, in case these observations are observed, which usually is accompanied by more complications, It is better to do an elective or planned surgical intervention to avoid these complications. Medical treatment in large cysts as such might not be effective. I think you gynecologist is right. Endoscopic techniques might not be very invasive today. Thanks and best regards, Luchuo. MD.