Suggest Treatment For Thickened Endometrium Along With Ovarian Cyst

Hi
I have just seen my doctor who says my endometrial lining is thickened at 13mm two days post ovulation. there is a cyst (only small) on one ovary also. Three years ago I had the other ovary removed because of a low malignant potential cancerous cyst. I get extremely light periods that last 12-24 hours. My lining was also thickened at my last check up a few months ago. He now wants to biopsy the lining and had recommended a full hysterectomy. Any thought please?
Many thanks
Jennifer