What Causes Recurrence Of Ovarian Cyst After A Surgery?

We get married in December 2007.

My wife get operated(Cesarian) in August 2009 for Ovarian Cyst.

But after operation Cyst is again developed. Now doctor has stopped menstrual for three months by giving medicines.

Doctor is saying that this is the course for 3 months and after three months I will check the response of medicine by Ultrasound.

I would like to know that what is the rate of success in this case to get pregnant.

Please reply