Not my area fred, but i will answer your question based on knowledge gained over a cheese and pickle sandwich and a pint of beer with mates who did know something about Ovarian Cysts OR you can Google it......;-)
Exceedingly common and usually benign (not cancerous) and would have thought that if one looked carefully (ultrasound etc) the almost all women with ovaries would have a cyst somewhere.....some more than others (Google polycystic ovaries)
They commonly disappear without treatment and if you have had one, it is very likely that you will have another at some time.
Only if it gives pain, ruptures or "bursts" will you require surgical treatment and my advice to you would be to keep your "reproductive organs" as long as possible.