I have polycyst in both ovaries size 4.09x2.87cm rt n 3.85x2.85 cm left is it harmful if not remove i m at metformin for 5 mnths?

Not usually harmful: If the cyst r are truly benign they are likely to go away on there own over time or with your medication. It sounds like you are being treated for polycystic ovarian syndrome which will frequently have persistent cyst. If you are not reassured it may be helpful to have your doctor draw a ca 125 level which can help evaluation for ovarian cancer. This is not likely in someone your age.