Hello mam, ovarian cyst
if more than 5 cm should be removed if it doesn't subside by itself in 3 months of medicines.
If it is causing discomfort and pain then it's better to remove it now which is a simple procedure and won't lead to removal of the ovary most probably.
As far as conception is concerned single ovary is also sufficient so relax for that side.
Take care and all the best.