Complex left pelvic cyst 5x4.6x4.6cm on scar of previous hysterectomy. is aspiration via us possible or is surgery better? abdominal pain and bloating

Cyst aspiration: If the cyst is aspirated is will refill with fluid over time. Surgery is a much better option.

Surgery: The cyst can be biopsied to determine why it is there, and rule out malignancy.

Surgery vs. Observe: Any post-menopausal woman with a complex pelvic cyst has to be careful for ovarian cancer; aspiration would be the last treatment option i'd consider unless you have morbidities that prevent you from having a safe surgery, i.e. Morbid obesity, cardiac failure, etc. I would either f/u w/ imaging in 3 mo's for growth of this cyst (unlikley) or accept surgical excision. Family history? Ca-125?