Why Is PCOS Ultrasound Suggested Inspite Of Not Being Pregnant?

Hi I took femilon from 30 the August 2013 to October 31st 2014. I got my last period on 6.11.2014 and went to the doctor and she prescribed me with Provera for induction of period as I was not pregnant. I want to know if this is because of OCP or is there any other reasons. Should I have to take a PCOS ultrasound? Or should I wait till I get my period?